To find records that satisfy multiple conditions in a single box, separate the search items with symbols:
| Symbol | Explanation |
| / | Represents Boolean OR. Expands a search, because EITHER condition may be met. Example: computer / network finds information about either of those topics. |
| & | Represents Boolean AND. Limits a search, because ALL conditions must be met. Use & if the retrieved records must satisfy several criteria at once. Example: computer & network finds topics only if they contain BOTH words. |
| ! | Represents Boolean NOT. Excludes records from the search results. Example: computer ! network finds topics that contain the word computer, but not network. |
Don't confuse AND and OR. The AND search will generally be a more specific search. A search for global&warming&greenhouse (using &) requires that each record contain all three words. The search global/warming/greenhouse (using /) requests any record containing any one of those words.
If the item for which you are searching includes characters that might be misinterpreted, surround the item with quotation marks. Example: search for "AT&T". When in doubt, use quotation marks.
You can include or omit spaces around the Boolean symbols (& / !). You can combine symbols in a box, and use parentheses to control the order of evaluation. Without parentheses, the conditions are evaluated in left-to-right order.
To find records that satisfy multiple conditions in more than one box, type information in each box. If the query form includes Boolean droplists next to the boxes, you can change the condition associated with that box.
| Boolean Command | Explanation |
| OR | Retrieves records that meet ANY of the criteria, such as all books written by Smith OR about climate, OR both. |
| AND | Retrieves only those records that meet ALL of the criteria, such as all books written by Smith AND which are about climate. |
| NOT | Excludes records from the search results, such as all books written by Smith which are NOT about climate. |
Search criteria in boxes are evaluated in top-to-bottom order.