FileMaker Go 19 crash

The best thing for this [to be sure that you don't need show all/omit all] is to run test cases to prove what works and how it works. Create a new file and set up a series of scripts that perform finds and have known outcomes and have the scripts validate those outcomes. You want to handle all the cases, including a search that fails. It's satisfying and may get you into the habit of writing test units.