Perhaps you should try some spelling variations:
trinh than » trinh thanh, trinh han, trinh toan
luan trong » quan trong, luat trong, luan tuong
hieu lang » chieu sang, hieu quang, nhieu tang
tang luan » dung luan
cho hieu » cao hieu, co hieu, chi hieu
anh tang » anh bang, anh dang, anh nang
than cau » toan cau, phan cau, than cap

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

• Performing a fuzzy search may retrieve terms with similar spellings: cho hieu lang - anh tang luan trong cong trinh than cau~.
• Adding a wildcard symbol may retrieve word variants: cho hieu lang - anh tang luan trong cong trinh than cau*.