Perhaps you should try some spelling variations:
hieu xanh » chieu xanh, hieu manh, hieu nganh
tranh vat » trinh vat, tranh va, tranh van
doc hieu » toc thieu, hoc thieu, hoc hien
vat dung » van dung, va dung, viet dung
cong dan » cong tan, huong dan, cong dong
cong san » cong tac
toan ban » van ban

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 xanh - canh tranh vat dung ((cong dan) or (cong san)) toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu xanh - canh tranh vat dung ((cong dan) OR (cong san)) toan ban.
• Adding a wildcard symbol may retrieve word variants: doc hieu xanh - canh tranh vat dung ((cong dan) or (cong san)) toan ban*.