Perhaps you should try some spelling variations:
phong chong » thong thong
chieu sang » chieu sach, chieu xanh, nhieu tang
phong cong » thong cong, chong cong, phong dong
hieu lang » hieu quang, nhieu tang, hieu van
canh tran » canh tranh, hanh trang, banh trang
tran van » luan van
tac toan » tap toan, tam toan, hach toan
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: doi ((chieu sang) or (hieu lang)) - canh tran van ((phong cong) OR (phong chong)) tac toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chieu sang) OR (hieu lang)) - canh tran van ((phong cong) OR (phong chong)) tac toan ban*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu sang) or (hieu lang)) - canh tran van ((phong cong) OR (phong chong)) tac toan ban*".