I tried searchmyfiles, and it's alright, but the best search tool I've found for windows is "Everything" by voidtools ( https://www.voidtools.com/support/everything/ )

I occasionally use it on a multi TB windows fileserver at work and after it does the initial index (which is really pretty fast because it uses the NTFS journals) searches are pretty much instantaneous. (I also use it at home, it's just less impressive after using it on that many files at work.)

If it works, don't fix it.