Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, hieu lang
nhung cong » dung cong, thong cong, hang cong
hieu quan » hieu qua, lieu quan, thien quan
tranh va » tranh van, trang va, trinh va
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan tap » toan ban

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 quan)) - canh tranh va nhung cong dan toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sang) OR (hieu quan)) - canh tranh va nhung cong dan toan tap.
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sang) or (hieu quan)) - canh tranh va nhung cong dan toan tap*.