If you read up about DHEA they say it can increase your sperm ejeculate but not to sure about the count, have you googled how to increase my sperm count, you just may find the answer there, there proberly some quite natural will help, that way no drugs.
Good Luck
1. Dont smoke, that's a big sperm killer.
2. Avoid wearing tight underwear, your balls are out of your body for a reason, to keep cooler then body tempreture, tight underwear pressed up against your 98.6° body is not a good idea.
3. Eat healthy!
4. Masturbate less, the more you do the less dense your semen will be.
5. Drink less alcohol
6. Exercise
7. Supplements can also help, L-carnitine, L-arginine, Folic acid.
Hope this information helps.