Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
hanh dung » thanh dung, anh dung, hanh dong
luan hung » luan chung, lan hung, luan ung
ho chieu » theo chieu, hoc thieu, mot chieu
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
than tap » toan tap, han tap, phan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) or (doi chieu)) xanh - hanh dung luan hung ((cong dan) OR (cong san)) than tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) xanh - hanh dung luan hung ((cong dan) OR (cong san)) than tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (doi chieu)) xanh - hanh dung luan hung ((cong dan) OR (cong san)) than tap".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (doi chieu)) xanh - hanh dung luan hung ((cong dan) OR (cong san)) than tap*.