Perhaps you should try some spelling variations:
khanh cong » thanh cong, hanh cong, khach cong
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
hanh luan » khanh luan, hang luan, hanh luat
van khanh » van thanh, van hanh, van anh
tap toan » tap quan, bai toan
tap doan » tap quan

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((hieu lang) or (chieu sang)) - hanh luan van khanh cong ((tap toan) or (tap doan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu lang) OR (chieu sang)) - hanh luan van khanh cong ((tap toan) OR (tap doan)) cau.
• Adding a wildcard symbol may retrieve word variants: ho ((hieu lang) or (chieu sang)) - hanh luan van khanh cong ((tap toan) or (tap doan)) cau*.