Perhaps you should try some spelling variations:
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
hanh trang » thanh trung, canh tranh, hanh trinh
trang tuan » tran tuan, trung tuan, trong tuan
tuan thong » toan thong, tran thong, tuan phong
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 trang tuan thong ((cong san) 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 trang tuan thong ((cong san) 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 trang tuan thong ((cong san) or (cong tac)) toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sang) OR (chieu sach)) - hanh trang tuan thong ((cong san) or (cong tac)) toan cau*.