Perhaps you should try some spelling variations:
thanh trung » thanh tung
trung tuan » trung thanh, trung tam, tran tuan
hieu sang » chieu sang, hieu quang, nhieu tang
hieu lang » chieu sang, hieu quang, nhieu tang
tuan dong » tuan duong, quan dong, luan dong
dong cong » duong cong, dung cong, dang cong
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cau » toan cau, phan cau, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu sang) or (hieu lang)) - thanh trung tuan dong cong tan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu sang) OR (hieu lang)) - thanh trung tuan dong cong tan than cau.
• Adding a wildcard symbol may retrieve word variants: doc ((hieu sang) or (hieu lang)) - thanh trung tuan dong cong tan than cau*.