There are supplements out there that promise to increase your libido while also upping your testosterone. There are over the counter testosterone supplements and prescription supplements. There are supplements that market themselves as T-boosters, while also touting themselves as an aphrodisiac. And then there are companies that claim to have developed a testosterone pill that contains the triumvirate of male-enhancing properties: T-boosting, libido-enhancing, and even fertility-increasing. These supplement makers sometimes throw in an additional claim of muscle gain as well.
The second theory is similar and is known as "evolutionary neuroandrogenic (ENA) theory of male aggression".   Testosterone and other androgens have evolved to masculinize a brain in order to be competitive even to the point of risking harm to the person and others. By doing so, individuals with masculinized brains as a result of pre-natal and adult life testosterone and androgens enhance their resource acquiring abilities in order to survive, attract and copulate with mates as much as possible.  The masculinization of the brain is not just mediated by testosterone levels at the adult stage, but also testosterone exposure in the womb as a fetus. Higher pre-natal testosterone indicated by a low digit ratio as well as adult testosterone levels increased risk of fouls or aggression among male players in a soccer game.  Studies have also found higher pre-natal testosterone or lower digit ratio to be correlated with higher aggression in males.     
Some, semi-common conditions that affect a good portion of society, and more who are non optimal excercisers: methylation problems (active folate, B12, b6 issues pyrroles (zinc, active b6, gla and some magnesium) (see Walsh protocols for a wide range of conditions from variouse malfunction, including sulphication issues, includes methylation) these are issues common in autism spectrum disorders, with Asperger’s being part of the disorder, I suspect trials on University students that be skewed by this), nor-adrenalin, copper vitamin C, iron or zinc and other issues, and people with ATP dysfunction, such as from the virus associated with chronic fatigue. Either a supplement addresses issues, or the underlying physiology might have to run smoothly to maximise it’s affect.