First of all stop using shampoos and soaps that have perfume and chemicals, use herbal soaps and shampoos...
Use seasame oil daily and along with that use Triphala, Tulsi, Sana Makki powder 3 grams in water daily once, this will provide zinc.
Tabeeb Khaja Azeemuddin (DMSS)
Shaafi Hair Oil Strengthens Hair Roots, Anti-Dandruff & Promotes Hair Growth. Natural And Free from All Side Effects.
Regular use of Shaafi Hair Oil will get back your hair to normal.