I think I was at about your level when I moved to Russia. The one thing that increased my vocabulary the most was translating, especially because news sites tend to use the same words (esp. verbs) over and over again. After you translate a few newspaper articles, you'll find that you don't need to look up certain words anymore, and eventually it will seem strange that you didn't know them before. Kind of like fake, sped-up immersion (because you are learning them in context, not from memorizing a list of words). 

It helps a lot if you HAVE to do this to get paid, but I would try it anyway. Start with a newspaper, though, because magazines are too fancy. Anything factual shouldn't give you too much difficulty. And no shame in using Google translate — I do.