Windows 10: Explorer search not working with additional HD

When you say "The Folders on my desktop search just fine" do you mean searching a folder with music in it gives you the results you want ?
If not, have you tried creating a new folder on your Desktop and copying a few songs to it then search the folder to see if it works how you want
If it doesn't work then I can't see how you can fix it other than finding 3rd party search software but I don't know of any that will do what you want