like: hệ thống âm vần
Intermediate Level Advanced Level
Composite Words Listening Comprehension Oxford Topics Duolingo Topics 315 Activities
BEGINNER LEVEL
exact:
VNEN 
hệ thống âm vần * ☊ 
syllabic system * ☊
[ hệ ] : branch, system; generation
[ âm ] : (1) sound; (2) lunar; (3) Yin, female, negative, minus; (4) reading (of a Chinese character)
[ vần ] : alphabet