Perhaps you should try some spelling variations:
chieu sang » chieu xanh, hieu lang, nhieu tang
chieu sach » chinh sach, chiet tach, chieu xanh
trung tuan » trung thanh, tran tuan, truong thanh
dung cong » dung trong
cong tac » cong ty
tac tran » tan tran, tac trai, tac tren
quang » quan

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

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