moi a e vao muc nay, can than coi chung nguy hiem...hehe
http://docs.google.com/present/view?id=0Adl9IxnQIBI9ZGhtN2t6MzVfMWZiY3NzbmN4&hl=viko co vius vào đọc nhé
http://docs.google.com/present/view?id=0Adl9IxnQIBI9ZGhtN2t6MzVfMWZiY3NzbmN4&hl=viko co vius vào đọc nhé