Smart folders aren't searching specific locations
I'm baffled. If I create a Smart Folder to search for say PDF files, it works fine if I select "This Mac", but as soon as I select a specific location such as my Documents folder (which absolutely contains PDF files), nothing shows up. What's going on? I've tried this with various locations and am absolutely certain the search criteria should be fulfilled. See screenshots attached.
Here it is working fine when searching "This Mac":
... and here I've selected my Documents folder not showing results: