Perhaps you should try some spelling variations:
hanh trang » thanh trung, canh tranh, hanh trinh
chieu sang » chieu sach, chieu xanh, nhieu tang
thong cong » trong cong, tong cong, thong thong
hieu lang » hieu quang, nhieu tang, hieu van
trang va » tran van, hang va
va thong » va thuong, va phuong, he thong
tac toan » tap toan, hach toan, tich toan
tam toan » tap toan, tam than, pham toan

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 lang)) - hanh trang va thong cong ((tac toan) or (tam toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu sang) OR (hieu lang)) - hanh trang va thong cong ((tac toan) OR (tam toan)) cau.
• Adding a wildcard symbol may retrieve word variants: ho ((chieu sang) or (hieu lang)) - hanh trang va thong cong ((tac toan) or (tam toan)) cau*.