Right now, it seems you need to focus more on your grammar. Try getting some good textbooks on English grammar, and work hard at it :)

You need to learn the basics first, and it takes time. Then, you can focus on expanding your vocabulary and improving your accent.

Reading books can help. Try reading some novels to get a grip on how English works. Reading text books can only bring you so far if you don't get any real world practice. So keep on practicing friend ;)

movies are the best way but you should know the grammar first

You might try the BBC: http://www.bbc.co.uk/learningenglish/vietnamese/