Perhaps you should try some spelling variations:
thanh trung » thanh tung
hieu lang » chieu sang, hieu quang, nhieu tang
trung cua » truong cua, trung tuan, trung cap
dung cong » dung trong
doi hieu » doi chieu, doc hieu, doi hien
cua dung » cua dang, cua dong, qua dung
cong dan » cong san, cong tan, huong dan
than cau » phan cau, than cap, thanh chau
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: doi hieu lang - thanh trung cua dung cong dan ((than cau) or (toan cau))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi hieu lang - thanh trung cua dung cong dan ((than cau) OR (toan cau)).
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - thanh trung cua dung cong dan ((than cau) or (toan cau))*.