There are many products (and even specific foods) that claim to boost testosterone, and there is some research to suggest that a few of these may do so. However, it’s likely not enough to put someone well outside of the normal physiological range, which is needed to provide real-world benefits of increased muscle mass.
For example, the normal range of testosterone in men is between 280 and 1100 ng/dL. Even though a product might be found to “increase testosterone by 25%,” for someone with a level of 800 ng/dL, this would push them to 1000 mg/dL, which wouldn’t give any major advantage to muscle building.
To put things in perspective, most studies showing significant benefits on muscle size and strength provided supraphysiological doses of testosterone (via injection) that increased blood testosterone levels by 500-600% (where levels were around 3000 ng/dL). Natural testosterone boosters (not the kind provided by injection) would never increase testosterone enough to have any significant impact on muscle building.