Perhaps you should try some spelling variations:
doi chieu » doi chi, ho chieu, mot chieu
tang luan » dung luan
doc hieu » toc thieu, hoc thieu, hoc hien
anh tang » anh bang, anh dang, anh nang
luan ung » luan hung, luon ung, luan chung
ung cong » dung cong, luong cong, duong cong
cong tac » cong ty
tac than » tac thanh, tam than, tac nhan
than cap » khan cap, thanh lap, thanh cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) or (doc hieu)) tinh - anh tang luan ung cong tac than cap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doc hieu)) tinh - anh tang luan ung cong tac than cap*.