What were the things you did? Did it improve testosterone levels too? If that is the mechanism, could you raise sperm count with artificial testosterone? Or would that be counterproductive?
This is why anabolic steroid users can develop shrunken (atrophied) testicles.
In addition, through enzymatic equilibrium, you will also produce more estrogen (excess testosterone is converted to estrogen and vice versa), which will further decrease male reproductive ability, and in sufficient quantities will stimulate breast gland growth.
In short, administering exogenous testosterone will have counterproductive reproductive consequences.