Mostly disobliging puppies pull away when on the leash. You can teach them better leash manners using lures, treats, praise, and games.
You need lot of patience with adult and non-cooperative dogs. You can reward their cooperation and obedience and correct them through their own resistance.
Use treats in your hand and move your hand forward luring him to move forward. Encourage your dog to follow the treat. It may help him walk forward.