Bedroom Double Doors How Can I Soundproof The Doors That Lead From My Bedroom To My Roommates' Bedroom?

How can I soundproof the doors that lead from my bedroom to my roommates' bedroom? - bedroom double doors

I live in an apartment-style station and one of my roommates has too many nights too strong. I do not want to leave, because I like it here, but I must do something about the noise! Is there a way to lower costs for noise, double doors to your room? The doors are made of wood. I can not replace because they lack the money, the more he will not live here permanently.