/ http://www.slideshare.net/images/logo.gif / ºÝºÝߣShare feed for ºÝºÝߣshows by User: Gnahkag https://cdn.slidesharecdn.com/profile-photo-Gnahkag-48x48.jpg?cb=1523569555 Phức tạp, khó khăn... lăng nhăng