I listened this song, i love this
Chac Ai Do Se Ve (OST Chang Trai Nam A)
Did Son Tung take the beat and pass it off as his own ?
No, This is a mistaken , Son Tung used some parts of the beat which like a song of Korean Singer. Not a stolen.
Hoi Nhac si Vietnam (Vietnam Composer Association) require Sơn Tùng to change beats of the begining part, then all things will be fine.
Chắc ai đó sẽ về (OST Chàng trai năm ấy)