Perhaps you should try some spelling variations:
hanh trinh » canh tranh
hieu sang » chieu sang, hieu lang, hieu quang
cua nhung » va nhung
doc hieu » toc thieu, hoc thieu, hoc hien
cong tan » cong tac, cong thanh, cong ty
cong san » cong tac
ran cau » van cau, ban cau, can cau

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 - ((hanh trinh) or (hanh chinh)) cua nhung ((cong tan) OR (cong san)) ran cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc hieu sang - ((hanh trinh) OR (hanh chinh)) cua nhung ((cong tan) OR (cong san)) ran cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc hieu sang - ((hanh trinh) or (hanh chinh)) cua nhung ((cong tan) OR (cong san)) ran cau".
• Adding a wildcard symbol may retrieve word variants: doc hieu sang - ((hanh trinh) or (hanh chinh)) cua nhung ((cong tan) OR (cong san)) ran cau*.