Perhaps you should try some spelling variations:
thanh trung » thanh tung
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, hieu quang, nhieu tang
trung cua » truong cua, trung tuan, trung cap
cua nhung » va nhung
ban thanh » ban hanh, ban hang
doi hieu » doi chieu, doc hieu, doi hien
dan chan » dan gian, dan ca, van chat

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: doi hieu lang - thanh trung cua nhung cong ((dan chan) OR (ban thanh)) cau~.
• Adding a wildcard symbol may retrieve word variants: doi hieu lang - thanh trung cua nhung cong ((dan chan) or (ban thanh)) cau*.