Google vs. Boolean Search Operators 
Being a former librarian, I decided to write a post about Boolean searching.  However as I researched the topic, I realized that exact Boolean searching is not used in most online search engines.  Therefore, I have summarized both Google Search Operators and Boolean Search Operators below. Boolean Search Operators will be used to search subscription databases at many libraries.

If students are going to use Google, why not use Google's advanced search tools?  Google has advanced search tools for text and for images that can be filled in to give great results. These can be found as follows:

But let's not end there.  There are many simple search operators that can be used in a Google Search that will give excellent results as well. If you use a custom Google search engine such as or these search operators will improve your results.

Search Operators for Google Search

1) To search for an exact word or phrase
Use quotation marks to search for an exact word or a set of words.  This works well if you are looking for a line from a book or poem, song lyrics, and if you are looking for an exact word or phrase.  You no longer have to use AND to put two words together in your search.
"Call me Ishmael"
"if I had a hammer"
"Abraham Lincoln"

2) To Exclude a Word
To exclude a word, use a minus or dash sign before the keyword in your search, such as if are looking for a cougar and you don’t want to include a car brand.  If you want to exclude a web site in the results, just type the keyword and follow it with the minus sign as follows:
cougar -car
cheetah speed -car

3) To Search Within a Site
If you want to search within a site or domain, just type the keyword followed by a space and the site name or the ending of the site, as follows:

4) To Search for Linked Pages
If you want to search for pages that link to a URL, just type in link: and the name of the URL.

5) To Search for Related URLs
To search  for pages that are similar to a URL, just type in related: and the name of a URL that you want to compare.
6) To Use a Wildcard
If you want to fill in the blank for a quotation or a phrase you are looking for, use an asterisk (*). Be sure to enclose the phrase in quotation marks. This is sometimes called a “wildcard.”
“Roses are * Violets are *”

7) To Use OR
To search for either word in a keyword search, use OR in all capital letters.
teenager OR adolescent
Boolean Searching

Boolean Searching is a useful way of entering search terms into a database to improve the quality of the results.  It is based on a method of logic developed by George Boole, a 19th century English mathematician. Because most databases  support Boolean searches, it allows you to more effectively select your search terms and thereby limit your results to obtain quality information.

Boolean operators include the following:


“AND” helps you to specify what you are searching for.  If you were searching for the word “cougar” and you only wanted results that includes animals, not the “new” connotation for the word, you could type the following into a search box.

cougar AND animal

“NOT” helps you to limit your search.  If you were searching for a “jaguar”, you might want to exclude automobiles from your search to limit the results.

jaguar NOT automobile

“OR” helps you utilize several terms for the same keyword search.  If you are searching for articles on teenagers, you might specify “teenagers” OR “adolescents” to improve your search results.

teenagers OR adolescents

If the search terms that you are looking for are usually adjacent to each other, try putting all the terms in quotation marks.  If you entered the words Abraham Lincoln in a search box, you would get a numbe of Abrahams and Lincolns, though not exclusively Abraham Lincoln.  Here is how to enter the adjacent search words:

“Abraham Lincoln”

If you want to group search terms for more complex searches, use parentheses, as follows:

fruit AND (orange OR grapefruit)
(teenagers OR adolescents) AND facebook

Resources for Boolean Searching

Colorado State University has a tutorial on using AND, OR, and NOT in Boolean Searching.

A project of the Board of Regents of the University System of Georgia

Boolean Searching Information from Penn State University

Library of Congress Online Catalog Help Page


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