Boolean operators are used by databases to focus searches. Three boolean operators are most recognized by database: AND, OR, NOT. When using the operators, use them in all CAPS.
Use OR to connect two or more similar concepts
It helps to broaden your search and retrieve more results
When using this operator, not all results will contain both concepts
Example: online learning OR distance education
Databases typically see AND as the primary operator and will connect search terms with AND first. To override the order, place the terms that you are connecting with OR in parentheses.
Most databases and search engines will search the statements within the parentheses first.
Example: (online learning OR distance education) AND zoom
This will search will retrieve results containing online learning and zoom, and also distance education and zoom.
Using quotes around keywords is called phrase searching. Not all databases or search engines use this, but it's a common way to search an exact phrase and get a more focused search.
Example: "online learning"