faster hair growth and new growth???

This question sounds a little bit crazy, so please bear with me.
I have been taking Biotin, Cod liver oil, MSM, Silica, amino acids and a multivitamin for several weeks now, and I was wondering what exactly it did for my hair.
I want my hair to grow faster ( I got my hair cut into a short bob about a month ago), and I want to regrow hair that seems to have just disappeared from my scalp. Okay, I'm exaggerating a little bit, but since I color my hair, I see less hair on my scalp, and in a lighted mirror I can see my scalp through the hair. When I mention this to family and friends, they say they can't really tell, but I know that my hair has been thinning out.
In short, will the supplements GROW my existing hair faster, or will they help new hair grow where it has fallen out and hasn't grown (since fallout)? Or will it do both? I know this is very confusing, but I still need a little advice on this. Thanks.