If you're not growing naturally, there is something wrong that you should address. Learning to understand your body is a useful skill that will be bringing dividends many years from now.

Steroids are a shortcut, but you should be moving in a correct direction. If you start doing roids, they will help you gain ~20-30 lbs. Add 20-30 lbs to a DYEL guy and he will look acceptable. Add 20-30 lbs to an okay looking dude and he will look amazing.

Here's personal story of a very good friend of mine (we are friends since both of us were 16).

My friend is 5'10" and was lean as fuck 165lbs (we both did track and field). When we turned 18 we both started lifting; he continued running, but I didn't. Two years later, after regularly going to the gym 2-3 times a week he was 170lbs (+5 lbs in 2 years). This is when he suspected that he is simply wasting time.

He spent next year trying to figure why the fuck doesn't he grow (he's not the smartest guy, unfortunately). It all boiled down to not eating enough and running too much. His BMR was ~2000 calories per day. His running (15 miles per week: 1 hour runs twice a week @ 7.5mph) was adding ~2000 calories a week, basically he was spending 16000 calories per week instead of 14000. He was eating ~300-500 calories surplus (/day) above his computed 2000 calories per day, and thus by the end of the week he consumed ~16100-17500 calories. Which after subtracting his BMR AND running, nets him 100-1500 calories week. This is barely a pound of muscle per month.

After he stopped running, he ballooned to 185lbs in 3-4 months and stayed there for a while. After he started lifting heavy (decreased reps from 10 to 5) he got to 195lbs.