Be sure not to miss the following facts about filters in Relativity:
Any term entered directly in the search box for a filter will be treated like a wildcard.
. . . if you enter an asterisk in the filter, it will be treated as a searchable character, and you may not get results for the stem preceding the asterisk.
You can use an underscore _ to search for a missing character:
Don't enter parentheses in a search for a phrase, just enter the phrase itself. Using an = sign before a term will run an exact search.