Go into Words and Wordplay listed under Education and Reference in Yahoo Answers.

You have to read quality books, not the typical adolescent stuff that is out there. As you read keep a dictionary, paper, and pen with you. When you find a word you don’t know put your finger on it. Then, at the end of the paragraph, write down the word, the sentence where it is found, and a guess at the meaning. When you get to the end of a chapter or section, look up all the new words you found and write down the entire dictionary entry for each word. Make flash cards from index cards with the word on one side and the definition on the other. Go over these every day. Use correctly every new word you find (several times each day). Make it a goal to learn and use one new word each day. If you find more than one, keep adding to your list. This is work, but it will increase your vocabulary. This is a system I teach my reading students and my international students who are trying to increase their English vocabulary.

Yes it does, as long as you look up the definitions of words you don’t know. If you come across an unfamiliar word, and just skip past it like it’s not even there then you aren’t learning any vocab.