Perhaps you should try some spelling variations:
theo chieu » theo tieu, theo chu, thi chieu
hanh trinh » canh tranh, hanh chinh
luat hang » luat chung, luat huong, luat thanh
luat hanh » luat hinh, luat canh, luat danh
ho chieu » hoc thieu, doi chieu, mot chieu
cong bai » cuong bai, cong hai, cung bai
bai toan » bai tap
toan cau » toan cao, toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((ho chieu) OR (theo chieu)) sach - hanh trinh ((luat hang) or (luat hanh)) cong bai toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (theo chieu)) sach - hanh trinh ((luat hang) OR (luat hanh)) cong bai toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (theo chieu)) sach - hanh trinh ((luat hang) or (luat hanh)) cong bai toan cau".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (theo chieu)) sach - hanh trinh ((luat hang) or (luat hanh)) cong bai toan cau*.