LibGuides: The Research Process: Search Techniques

Search Strategies

Terminology searching focuses on the words that you use when conducting a search.

Keyword
The most common type of search is a keyword search. This is when you type a word into the search box and click "Search" without adding any additional information, that is a keyword search. For example: flu

Phrase
Phrase searching is similar to keyword searching, but instead of searching for one word, you're searching for a phrase. Phrases are surrounded by quotation marks to keep the words of the phrase together, otherwise the search interface will usually search for the words separately, anywhere, not necessarily together. For example, searching for "walking pneumonia" -including the quotations marks- will search for the phrase together instead of the word walking in one location and pneumonia in another location.

Proximity
Proximity searching enables you to search for two or more words that occur close to one another in a database.The number in the search phrase tells the search interface how many words away from each other the search terms can be. This allows a limited number of other words to be placed between the search terms, providing more possibilities for search retrieval within a limited scope.
Near operators, usually using the letter N, search for words in any order. For example,
Within operators, usually using the letter W, search for words in the order you place them. For example,

Here’s the order of terminology search types based on restrictions placed upon the search.

Keyword searches = no restrictions. The database can search for the terms in any order and at any distance from each other.
Proximity searches = some restrictions. The database can search for the terms either in any order (near) or in a specific order (within). The database is restricted to allowing a limited number of other words to appear between the search terms (the number in the proximity operator).
Phrase searches = restricted. The database must search for the terms in the order provided with no other words being allowed to appear between the search terms that are placed in quotation marks.

Boolean operators define the relationship between search terms. When you use a Boolean search, keywords are combined by the operators AND, OR, and NOT. You can use these operators in the database search interface to create a very broad or very narrow search.

AND combines search terms so that each search result contains all of the terms. The AND operator limits the search because the sources in the results must contain both terms.
OR combines search terms so that each search result contains at least one of the terms. The OR operator expands the search because the sources in the results can contain either term.
NOT excludes terms so that each search result does not contain any of the terms that follow the NOT operator. The NOT operator limits the search because the sources in the results cannot include the term following the word NOT.

Below are a few diagrams illustrating how Boolean operators limit or expand searches.

image Venn diagrams

Wildcard searching replaces the wildcard character with any other character or characters, or sometimes no characters. Common wildcard characters include the asterisk (*), pound sign or hashtag (#), or question mark (?). Some databases accept multiple wildcard characters. Others only accept one or two. Be sure to check the database's "Help" page to find out this information.

For example, a search for b*rn finds both born and bourn; it can also expand more than that.

Truncation searching is a specific type of wildcard search that replaces the wildcard character with any other character or series of characters at the end of the word. Truncation characters are almost always asterisks (*).

For example, a search for direc* finds director, direct, direction, etc.

Field terms are words or phrases located in an item's record according to a specific type, or field. To search according to field term, select the field from the drop-down menu next to the search box.

A keyword search looks for your search terms anywhere in an item's record. They could be in an author's name, a title, an abstract, or somewhere in the technical coding. Keyword searches are automatic in most search systems. If you don't see an option for "Keyword" in the drop-down menu, then the search interface will search by keyword in its default setting.
An author search looks for your search terms ONLY in the author fields for an item's record. Sources have different types of author fields: main author, translator, editor, etc. This search will look in all of those fields.
A title search looks for your search terms ONLY in the title fields for an item's record. Sources also have different types of title fields: main title, subtitle, series title, etc. This search will usually look in all of those fields.
A subject search looks for your search terms ONLY in the subjects for an item's record. This usually means a search in the system's controlled vocabulary. (Controlled vocabularies are like specialized thesauri. Organizations agree to use one word or phrase to describe an idea. From there, indexers will associate the controlled vocabulary with sources. For example, instead of movie, film, video, motion picture, a catalog would only use the phrase motion picture to describe all of those things.) Because subject searches are more precise, they usually return more relevant results.
- Remember that MeSH terms are specialized subject terms!
A search in the ISSN/ISBN/OCLC field searches for specific numbers.
- An ISSN is an International Standard Serial Number, which is used to identify serial publications, such as journals or magazines.
- An ISBN is an International Standard Book Number, which is used to identify books.
- OCLC stands for Online Computer Library Center. The OCLC number is a specific number used to identify materials cataloged in the OCLC network of libraries. Many, but not all, items will have this number.

These are the main field search limiters that will appear in most search systems. Many databases will have additional field terms, such as geographic locations or other numeric codes. Explore the drop-down menus to find out what’s available.

Understanding Keywords

Search library databases using keywords, such as concepts or subject phrases that are linked together by and, or, not (explained below) used to identify articles and sources. Once you have identified your topic, selecting your keywords is pretty simple.

1. Divide your topic into concepts/segments/pieces.

In the question, "What is the relationship between diabetes and eating sugar?," the concepts are: diabetes, sugar, and health

2. Brainstorm for synonyms and related terms.

You will need to translate these terms to keywords later when you are searching databases for articles and sources. Even if a combination of words works well in one database, you may have to change keywords to find results in another database.

3. Create your search by combining your keywords using an, or, not. (This is described above in the Boolean tab)

3. Follow the database-specific language.

As you do your searching, keep track of the words that appear in the detailed descriptions, or records, of your results list in the fields that will be labeled with headings such as subjects, descriptors, or subject headings. These synonyms and related terms are the specific vocabulary used to describe your search term in that database or discipline. Using these in your search can often improve your search by making it more accurate and efficient.