Perhaps you should try some spelling variations:
thien hieu » thien nhien, thien chien, thien hue
hieu lang » chieu sang, hieu quang, nhieu tang
dung cong » dung trong
manh toan » thanh toan, anh tuan, tinh toan
hanh ban » thanh ban, hang ban, hanh san
tam toan » tap toan, tam than, pham toan
va dung » van dung, va duong, vat dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: thien hieu lang - hanh ban va dung cong ((tam toan) or (manh toan)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thien hieu lang - hanh ban va dung cong ((tam toan) OR (manh toan)) ban.
• Adding a wildcard symbol may retrieve word variants: thien hieu lang - hanh ban va dung cong ((tam toan) or (manh toan)) ban*.