In the Compatibility Checker application shipped with System 7 Pro, AppleSearch's compatibility state is listed as not known, because at the time the Compatibility Checker's data was frozen, AppleSearch had not yet been released.
AppleSearch 1.0 has been tested against System 7.1 Pro as well as all current Macintosh computers (including the AV machines) and there are no known compatibility issues. A future version of the Compatibility Checker will be corrected to show this fact.