Perhaps you should try some spelling variations:
nhanh dong » hanh dong, nhanh chong, anh dong
dong chuan » dong chan, dong thuan, dong chuyen
hieu sang » chieu sang, hieu lang, hieu quang
cong cong » cong dong, trong cong, dung cong
dang cong » dung cong
doc hieu » toc thieu, hoc thieu, hoc hien
van van » tan van, san van, van vat

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: doc hieu sang - nhanh dong chuan ((cong cong) or (dang cong)) van van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sang - nhanh dong chuan ((cong cong) OR (dang cong)) van van ban*.