Perhaps you should try some spelling variations:
chieu tinh » trieu tinh, lieu tinh, chau tinh
chieu sang » chieu sach, chieu xanh, hieu lang
hanh trung » thanh trung, hanh trang, manh trung
trung va » truong va, trang va, trung ha
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 tinh) or (chieu sang)) - hanh trung va nhung ((cong tan) or (cong tac)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu tinh) OR (chieu sang)) - hanh trung va nhung ((cong tan) OR (cong tac)) toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu tinh) or (chieu sang)) - hanh trung va nhung ((cong tan) or (cong tac)) toan cau*.