Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu sach, chieu xanh, nhieu tang
trung tuan » trung thanh, trung tam, tran tuan
hieu lang » hieu quang, nhieu tang, hieu van
tuan dung » tuan duong, tran dung, tan dung
cong tan » cong tac, cong san, cong thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: thien ((chieu sang) OR (hieu lang)) - thanh trung tuan dung ((huong dan) or (cong tan)) van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thien ((chieu sang) OR (hieu lang)) - thanh trung tuan dung ((huong dan) OR (cong tan)) van ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thien ((chieu sang) OR (hieu lang)) - thanh trung tuan dung ((huong dan) or (cong tan)) van ban".
• Adding a wildcard symbol may retrieve word variants: thien ((chieu sang) OR (hieu lang)) - thanh trung tuan dung ((huong dan) or (cong tan)) van ban*.