Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu sach, chieu xanh, nhieu tang
khong cong » thong cong, khong cang, chong cong
hieu lang » hieu quang, nhieu tang, hieu van
trung hua » trung ha, trung hoa, trung cua
hua khong » hoa khong, cua khong, hoac khong
tan thanh » tran thanh, tang thanh, toan thanh
tan than » tan tran, ban than, tam than

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: ho ((chieu sang) OR (hieu lang)) - thanh trung hua khong cong ((tan than) OR (tan thanh)) cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((chieu sang) OR (hieu lang)) - thanh trung hua khong cong ((tan than) or (tan thanh)) cau~".
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sang) OR (hieu lang)) - thanh trung hua khong cong ((tan than) or (tan thanh)) cau*.