Image source: Wikimedia Commons. Public domain.
Boolean operators (AND, OR, and NOT) are used to connect keywords and concepts when searching.
|AND|| Florida AND hurricanes
|| Retrieves records that contain
BOTH hurricanes AND Florida
hurricanes OR tornadoes
| Retrieves records that contain
EITHER of the search terms, but
does not necessarily include
all of them.
eruption NOT limnic
| Excludes records containing
the second search term.
If your initial search does not produce the desired results, try:
Keep search queries simple and descriptive; use as few terms as possible. Avoid natural language queries (What were the monetary damages and human impacts of Hurricane Katrina?) as they can limit your results. Use "hurricane katrina" AND damage, or "hurricane katrina" AND human.
Use double quotation marks ("Hurricane Katrina") to search terms as a phrase and focus your results. Remember that a search of "Hurricane Katrina" will retrieve only those pieces of information that refer to Hurricane Katrina exactly like that. Citations that use simply Katrina will not be retrieved.
In Google, use site: to limit your results to a specific website or website domain. The query Hurricane Katrina site:gov will only retrieve information about Hurricane Katrina from U.S. Government websites. In library databases, try limiting to academic sources or by publication year.
In Google, to remove unwanted search terms, place an - in front of the term you don't want. For example: eruptions -limnic will find information on eruptions, but not limnic eruptions. In library databases change the AND to a NOT, and enter the term you want to exclude in the search box after the NOT.
Good searchers always think of synonyms to include in their searches. When you search for synonyms in library databases, keep your synonyms on the SAME line and connect them with OR.
Library databases do not automatically truncate--you'll need to use help to figure out the symbol used to truncate, Truncators will search for all variant word endings. For example, in EBSCO databases, one can truncate using *: searching for erupt* will retrieve erupt, erupts, eruptions, eruptions, erupted.