Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu xanh
chieu sang » chieu xanh, hieu lang, nhieu tang
hanh hang » thanh hang, hang hang, hanh han
cong tan » cong san, cong thanh, cong ty
cong tac » cong ty
tran cau » tran chau, toan cau, ran cau
va dung » van dung, va duong, vat dung

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 sach) or (chieu sang)) - hanh hang va dung ((cong tan) OR (cong tac)) tran cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sach) OR (chieu sang)) - hanh hang va dung ((cong tan) OR (cong tac)) tran cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sach) or (chieu sang)) - hanh hang va dung ((cong tan) OR (cong tac)) tran cau".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sach) or (chieu sang)) - hanh hang va dung ((cong tan) OR (cong tac)) tran cau*.