I have White Bumps On My Shoulder and Sometimes By Back But They Don't Pop What Could it Be? (photo)

Hey im now 21 year old male.... i have these white bumps on my shoulder are and sometimes in middle of my back when they breakout but thats once in a while. I have seen a determoglist and he gave me a script for Minoclyine i believe and triycoline pills which diddnt work. These bumps are unpopable and bother cause htere all voer and ugly to the skin. I had these for about about 7-8 years as i can reamber and just dont know what there from or what there called period. Can Someone Please help me.