Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
hieu quang » thieu quang, hieu quan, hieu qua
trung tuan » trung thanh, trung tam, truong thanh
tran tuan » tran xuan, tran quang, tran thanh
cong tan » cong tac, cong san, cong thanh
tan khan » tan khang, tan nhan, toan khoan
khan dam » thanh dam, chang dam, khanh nam

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

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