Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, nhieu tang
tranh luat » trinh luat, tranh luan, trinh luan
luat nhung » luat chung, luat thuong, thuat nhung
nhung cong » dung cong, thong cong, hang cong
hieu lang » hieu quang, nhieu tang, hieu van
tap toan » tap quan, bai toan
tap doan » tap quan

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: theo ((chieu sang) OR (hieu lang)) - canh tranh luat nhung cong ((tap toan) OR (tap doan)) tap~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((chieu sang) or (hieu lang)) - canh tranh luat nhung cong ((tap toan) OR (tap doan)) tap~".
• Adding a wildcard symbol may retrieve word variants: theo ((chieu sang) or (hieu lang)) - canh tranh luat nhung cong ((tap toan) OR (tap doan)) tap*.