I have always agreed with the sayin that language is not something you learn but you absorb. I think it works the same way here. About these English proficiency tests, you should be able to pass them if you can read, write, and speak English fluently. After all, they are PROFICIENCY tests. So I suggest you just submerge yourself in English rather than "study" for them. Start watching American shows; tv-links.eu is a great link for any American show you wan to watch. Start with romance, action or mystery genres, then go into detective. Once you are able to fully comprehend jokes and punch lines on a comedy shows like SNL then at that moment you can call yourself trully fluent in the language, which means you should easily be able to pass TOEIC and other proficiency tests. Good luck!