Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, nhieu tang
thanh tung » thanh cong
nhung cong » dung cong, thong cong, hang cong
hieu lang » hieu quang, nhieu tang, hieu van
manh toan » thanh toan, anh tuan, tinh toan
tung cam » dung cam, trung cap, tung pham
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu lang) OR (chieu sang)) - thanh tung cam ((nhung cong) or (thong thong)) manh toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu lang) OR (chieu sang)) - thanh tung cam ((nhung cong) OR (thong thong)) manh toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu lang) OR (chieu sang)) - thanh tung cam ((nhung cong) or (thong thong)) manh toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu lang) OR (chieu sang)) - thanh tung cam ((nhung cong) or (thong thong)) manh toan ban*.