Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
hanh trinh » canh tranh, hanh chinh
mot chieu » doi chieu, ho chieu
van thanh » ban thanh, van tuan
doc hieu » toc thieu, hoc thieu, hoc hien
trinh va » trinh van, trinh vat, trinh ve
dan toan » van toan, dan than, manh toan

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((mot chieu) or (doc hieu)) sach - hanh trinh va nhung cong ((dan toan) or (van thanh)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((mot chieu) OR (doc hieu)) sach - hanh trinh va nhung cong ((dan toan) OR (van thanh)) cau.
• Adding a wildcard symbol may retrieve word variants: ((mot chieu) or (doc hieu)) sach - hanh trinh va nhung cong ((dan toan) or (van thanh)) cau*.