Email Filter [Apply to email in folder]

When creating a filter in Usermin there are several buttons at the bottom one being [Apply to email folder] and then 2 dropdowns allowing you to pick which folder to use.
Why are there 2 dropdown choices?
When I select the button (with dropdowns set to inbox) it can’t locate any emails that match the criteria specified in my filter.

Also, I would think that it might be handy to be able to select several different filters from the list of filters and then run these on your selected folder. Is this possible?

Thanks for any help


Here is a related post I sent to Help (Newbies) a few months ago: