like: vô hiệu
Intermediate Level Advanced Level
Composite Words Listening Comprehension Oxford Topics Duolingo Topics 315 Activities
BEGINNER LEVEL
exact:
VNEN 
vô hiệu * ☊ 
ineffective, ineffectual, without effect * ☊
[ vô ] : (1) in-, im-, (negative prefix); (2) in, at, on; (3) to go into, enter [= vào]
[ hiệu ] : store, shop; sign, signal, mark, brand, trademark