like: khảo cứu
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Composite Words Listening Comprehension Oxford Topics Duolingo Topics 315 Activities
BEGINNER LEVEL
exact:
VNEN 
khảo cứu * ☊ 
to investigate, study, research; study, inquiry, investigation * ☊
[ khảo ] : to do research; to examine, test (students); torture, extort
[ cứu ] : (1) to save, rescue, deliver, relieve; (2) to study, research, examine, investigate