If you have a leak in your game, say whether it's chasing draws to often or 3-betting too light for instance, then your best bet is to go and look at some of your hand histories. There you can go over any hand street by street to see if you played your
hands correctly or whether you could of improved. By doing some extra work and going over some hand histories, you can find the leaks in your game and find or realise the right solution to plug those leaks. Hope this helps.