I wouldn't exactly say that all of the previous posts failed, but this situation does happens a lot of the time. A guy asks "'Bodypart Z' isn't growing. What should I do?" Other guys start from that question and run forward, when really, it's usually more important to take a look at the bigger picture.
No offense to Philly, but we don't know his age, height, weight, or lifting experience. Maybe he's been lifting for two months. Maybe he's 137 pounds. Not that we need a novel for every question asked, but basic profile info would be a great start.