In a tab:
- Go to Menu:Commands > Search (or Alt-F7)
- Enter some search query (tested with: ev: ext:exe c:\program )
- Press Start Search (or Alt-s)
- Press the Feed to Listbox button (or Alt-L)
So far, so good ..
- Go to Menu:Commands > Search (or Alt-F7)
- Enter a different search query (tested with: ev: ext:ini c:\program )
- Press Start Search (or Alt-s)

When doing this new search in a "fresh" tab, results are as expected (ie: shows INI files instead of EXE files)
I am just mentioning this. I don't use Total Commander often enough for this to be fixed (if it is broken; not sure)