You could try totalcommander (
www.ghisler.com)
First change to the folder with the files, compressed folders and compressed files, then to open the search dialog press:
[Alt-F7] Specify wildcard for the files you want to copy e.g.
*.stl(Optionally Enter a string you are looking for in those files, to limit the result)
Check the box before
[
v] Search a
rchives (except for UC2)
Press button
[Start search] ..wait.. then when the list of files is shown press
[Feed to listbox]All filenames are now shown in the normal tc window.
Select the destination folder in the other window
..
To copy the files to the destionation folder. Go back to the window with the search results, and select some or all of the files, press
[F5]ready