What is the best and effective way to thicken or regrow hair?

I used to have thick and healthy hair when I was in high school but as I grow older my hair seems to vanish!I feel devastated every time someone notices how thin my hair is!Please help me.I'm almost close to becoming bald!What is the best and effective way to thicken or regrow hair?
Use Clinique Hair Maximzing Shampoo and Hair Maximizing Serum.

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