Perhaps you should try some spelling variations:
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
hanh trung » thanh trung, hanh trang, manh trung
trung quan » truong quan, trong quan, trung tuan
quan nhung » qua nhung, cua nhung, luan chung
cong tan » cong san, cong thanh, cong ty
cong tac » cong ty
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chieu sang) or (chieu sach)) - hanh trung quan nhung ((cong tan) OR (cong tac)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sang) OR (chieu sach)) - hanh trung quan nhung ((cong tan) OR (cong tac)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sang) or (chieu sach)) - hanh trung quan nhung ((cong tan) OR (cong tac)) toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) or (chieu sach)) - hanh trung quan nhung ((cong tan) OR (cong tac)) toan cau*.