To exclude bak files in Finder's search? I create bak files after every Perl operation.

How can you exclude all bak files in your Finder's search?
The answer to this question is to add .noindex -extension at the end of .bak. Thank you, Tetsujin!
I refer this one liner to do it

find . -name "*\.tex" -exec bash -c 'mv "{}" "{}.noindex"' \;