Find not working

This is driving me mad. I’m using the Find tool and getting “not found”.

I keep getting “not found” when searching for hyphenated words like duty-free and check-in. And then I just get the same “not found” when I search for a word I can see in the text! Even when I click inside the text 'area, it still gives me “not found”. I just searched for the number “21” (I can see it in the text) but it says “not found”.

Scrivener (Mac version 2.54)
Mac OS 10.8.5

Does this persist if you restart the software? If not, check this thread for a potential solution.