In my humble opinion, it's very important to 'memorize' as many expressions as you can. By 'memorize', I mean that you should try to get yourself used to those expressions. It's just the way babies learn language. You said you're trying to listen to English news and to read English article, and so on. I think that's good. But if you try to 'memorize' some unfamiliar expressions to you, that would be better I guess. And..maybe this is the best thing you can do, as long as you don't live in English-speaking environment. Good luck to you.