Boolean is a set of commands that can be used in almost every search engine, database, or online catalogue. The most popular Boolean commands are AND, OR, and NOT. Other commands include parentheses, truncation, and phrases.
Narrow your search using AND
Using the Boolean command AND in your search tells the search engine to give you results that contain all of the words you have entered.
Example
media AND violence: only those results that contain both media and violence will appear in your search results list.