Perhaps you should try some spelling variations:
chieu xanh » chieu sach, chieu sang, hieu manh
chieu tinh » trieu tinh, lieu tinh, chau tinh
trung hoc » trung quoc
dung cong » dung trong
trung ha » trung tam, trung cap
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cao » toan cao, thai cao, than cap

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu xanh) OR (chieu tinh)) - hanh ((trung ha) OR (trung hoc)) dung cong tan than cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu xanh) OR (chieu tinh)) - hanh ((trung ha) or (trung hoc)) dung cong tan than cao~".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu xanh) OR (chieu tinh)) - hanh ((trung ha) or (trung hoc)) dung cong tan than cao*.