Efter lite sökande hittade jag denna diskussion som hjälpte mig att skapa en sökning som inkluderar systemfiler:
Apple - Support - Discussions - Spotlight doesn't find things ...,
Det viktiga inlägget är:
"CMD+F, click on Kind button, select Other, drill down to File invisible, check it, continue down to System files, check it, and click OK. Now, click on + button, click on the left-hand item and select System files and select are included, click on the plus button, click on the left-hand item and select File visibility and select visible or invisible, select File Name, save the search"