Why can't I get what Americans say ? ?

I am Indian. My first language is not english but it will not be too difficult to speak with fluency. I am working hard and soon will work this out. To make my englis better I use to watch hollywood movies animations too. I also listen to english songs but hardly make out what's being said. When I saw the movie `Kung Fu Panda and KFP 2' made out almost everything but when I watched another movies like Resident Evil or Rob b hood and others, hardly I get a word what they say. I know english and also can speak but why is this kind of problem occuring?