Thick, Lush, Hair..................?

My best friend has sooooo much hair and it is thick and lush even when its wet it dries lush! i have kind of thin hair and I hate it. I have always hated it and it barely grows! I have tried many different shampoo's and cut down on the heat for about 3 years now ! I have even been taking biotin and massaging my scalp daily and my hair is still the same. What should I do? I want lush thick hair really bad and I would do anything to get it ! how do I get lush hair?