Hair Growth Remedies

I’m not talking a miracle hair growth vitamin or anything like that. I’m also not talking about something that would make my hair grow insanely fast because I know that’s not possible. I’m asking what vitamin, you know like A B C D ect… that would promote hair growth…my hair doesn’t grow at a normal rate these days and Im thinking that I may be missing something in my diet??? So what vitamin if any is know for promoting heathly hair growth and nail growth ect?