I don't think youll find a "trick" like this really.
Anything you do won't really give you a hugely explosive increase in results.
I remember reading somewhere certain kinds of meditation have been proven to increase concentration (you can look it up on wikipedia if you like).
You could try some suppliments or something
here.Whatever you do though, it will be subtle. You won't get the explosive increase in concentration you're looking for.
Really, be weary of what people tell you. You aren't suddenly going to gain mental super powers.
Humans aren't really engineered for this sort of thing anyway, for most of existence we've been more focused on dealing with the immediate as in "Oh, shit dude is that a tiger over there?" rather than sitting down and sharing study tips with the tiger... you see my point right?