Boolean Operators AND, OR, and NOT connect each keyword and/or keyword phrase in a statement such as: What is the relationship between United States intelligence operations and counterterrorism?
In the following examples, circles and areas in the Venn Diagrams that appear purple are returned as search results by the database.
Use AND to narrow a search strategy and to look for two or more terms in your result.
Example: United States AND counterterrorism
Use OR to broaden a search and to find either or both concepts in the result.
Example: counterterrorism OR counter terrorism
In this case, every article with either "counter terrorism" or "counterterrorism" is returned in the list of results.