Does anyone know how to get deep stains out of floor tile?

I've tried stripping solutions from home depot, Didn't work. Scrubbing with scrubbers, didn't work. Magic eraser, did a little bit better but still didn't work. I've tried mopping it with bleach, mopping with vinegar and baking soda, mopping with mean green cleaner and degreaser. Nothing works! There has to be something I can do.