Perhaps you should try some spelling variations:
theo chieu » theo tieu, ho chieu, theo chu
nhung cong » dung cong, thong cong, hang cong
mot chieu » doi chieu, ho chieu
hanh tang » hanh trang, anh tang, hanh mang
tap toan » tap doan, tap quan, bai toan
van toan » van tuan, van tan, van thanh
tang va » trang va, tang van, thang va

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

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