Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
trung cam » trung tam, trung cap, trung nam
thanh cac » hanh cac, thanh bac, thanh ca
cam hung » cac chung, cam nang, van hung
cong ban » cong bang, cong tan, cong dan
cong san » cong tac

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