you look like an ectomorph type bro, you might be training it hard and having trouble but thats exactly what you are doing wrong, ectomorphs struggle to gain anyways, low volume is the best way to train, and start eating more, from your picture is does not look like you are eating big, taller guys struggle to gain decent mass unless you are genetically well off, im 6ft 4 and 16.5-17 stone right now, up from like 15stone before i started training properly, its only taken me a couple years to get there..but you'd be suprised how big a difference your diet and intensity of your training effect your recovery, steroids or no steroids....
back to basics, low volume/compound exercises/4-8 rep range to improve strength/
3-4 days tops lifting each week ( sounds like not a lot but you have to try these things before you can argue that point ), minimal cardio....
check out these links i think they may help you:
Fitness & Physique Magazine
Bodybuilding.com - Paul Becker - What Is Your Body Type? Take Our Test!