Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
trinh luan » trinh luat, trinh quan, trinh han
doi chieu » doc hieu, doi chi, mot chieu
luan nhan » luan phan, luan nha, xuan nhan
tuong dan » huong dan, xuong dan, truong dai
ho chieu » theo chieu, hoc thieu, mot chieu
tung dan » dung dan, huong dan, trung dai
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 (doi chieu)) sach - hanh trinh luan nhan ((tuong dan) OR (tung dan)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (doi chieu)) sach - hanh trinh luan nhan ((tuong dan) OR (tung dan)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (doi chieu)) sach - hanh trinh luan nhan ((tuong dan) OR (tung dan)) toan cau".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (doi chieu)) sach - hanh trinh luan nhan ((tuong dan) OR (tung dan)) toan cau*.