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