sao tui share rui ma ko down dc ban co the share cho minh dc ko:nick cua minh:ca_map_n@yahoo.com; cam on bac nha;minh dang rat can bai tap do an...
cac bac giup minh ve bai tap pttkhthong dc ko mon nay minh chiu chang bit gi? bac nao co the huong dan voi nha .thanks...ca bac.