Questions Regarding Advanced Case Search

Hi! I am reassigning cases to different case owners by using the advanced case search method referenced in this wiki here:

Advanced Case Search - CommCare Public - Global Site.

Is it possible to search cases by the form ID (formid) or the usercase ID (e.g. ? The wiki only shows syntax for how to search for cases by name, the lack of a name, case ID, case type, dates, or by whether or not a case is open or closed. I tried to use _formid: to search for relevant cases, but using that syntax did not seem to yield any results. Any input regarding this would be much appreciated. Thanks so much for reading!