First things first: Close the MobileSheets app and open your tablet's file manager.
Joe, is the problem that you can't locate the original .pdf files in your tablet's file system... or that you can't print them once you find them?
If you can't locate them, please let us know how the files got on your tablet in the first place: did you copy them from a computer, download them in the tablet's browser, send them by email, put them in Dropbox? Did you use the MobileSheets Companion software? We need that info to figure out where the files are stored. It is likely but not certain that the original .pdf files are still on your tablet somewhere.
If the problem is opening the file and printing it, tell us if you already have the tablet and printer set up to communicate. Is this the first thing you've tried to print?