How can I make KDE respect my choices for download location
I use different browsers to do different tasks, but downloading a file/image goes where ever location I used last, ignoring what I set my browsers download location to be

I have 20'000 mostly mp4 or webm files
I used a naming scheme that has the last two digits signifying different criteria about the video
example joe 24070, joe 24050, joe 24051
joe 24051 is a revised edit of joe 24050
The first in the series of joe is joe 100, joe 110, joe 140

As an example I would like to sort all files ending in 50, 51, 52, 53, 54, 55, 56, 57, 58, 59
I can't specify a set number of characters as it changes as more content is added to the end of the series Kfind will do a dandy job of searching folders & subfolders, how would I set the search criteria?
Is there some other GUI tool?