Why am i still getting hair breakage?

i use Dove shampoo and conditioner that is for hair recovery, then i get out of the shower and use Tresemme hair thermal or something to protect my hair from heat, then i brush through it with a com like this: http://www.blueheronwoods.com/images/C/HairComb.jpg (except plastic) and i let it air dry. i don't understand why i'm getting hair breakage still?