Bulk Rename Utility

Let's say I want to find the following text in a filename: AK (one word; all caps).

I want to do this, so that I can find only the files with those exact letters in the filename.

How do I do this?

I tried using Filters (12), but it found nothing. I tried selecting "Match Case" and selecting all the folders -- and, still, it found nothing.

Any ideas?

Thanks!

Inside of Filters(12), there must be a checkmark inside for "Match Case", so then a "Mask" like... *AK*
If AK must be 1 exact word?, then must add a checkmark for "RegEx", and then a "Mask" like... .*\bAK\b.*
After typing any new text into the "Mask", can click the nearby blue-arrows to conduct your Masks!