Hi chienvlqt,
Do you plan to take the GMAT as well? If yes, get started with the RC passages and try to understand them. Rephrase the main ideas in your own words. That forces you to really understand what you just read. If you understand these passages, the TOEFL passages are a piece of cake.
A great platform to study is Englishtown.com, because they combine writing, reading and listening in a very relaxed atmosphere with a new topic every day. That will increase your vocabulary without having to study long lists of them.
They offer also dedicated TOEFL prep, which helped me to score in the 92th percentile.
Hope that helps.
Jochen