Perhaps you should try some spelling variations:
theo chieu » theo tieu, theo chu, thi chieu
hanh trinh » canh tranh, hanh chinh
cuong tap » luong tap, cong tac, luong tai
ho chieu » hoc thieu, doi chieu, mot chieu
cua rung » cua trung, cua rang, cua truong
tap toan » tap doan, tap quan, bai toan
toan ban » van ban

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 (ho chieu)) sach - hanh trinh ((cua rung) or (cua ban)) cuong tap toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((theo chieu) OR (ho chieu)) sach - hanh trinh ((cua rung) OR (cua ban)) cuong tap toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((theo chieu) OR (ho chieu)) sach - hanh trinh ((cua rung) or (cua ban)) cuong tap toan ban".
• Adding a wildcard symbol may retrieve word variants: ((theo chieu) OR (ho chieu)) sach - hanh trinh ((cua rung) or (cua ban)) cuong tap toan ban*.