Perhaps you should try some spelling variations:
thiet nhung » tuyet nhung, thi nhung, biet nhung
trinh thiet » trinh viet, trinh thi
hanh trinh » canh tranh, hanh chinh
hoc thieu » toc thieu, hoc hien
ho chieu » theo chieu, doi chieu, mot chieu
cong van » cong vang, song van, cong tan
cong san » cong tac
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 (hoc thieu)) sach - hanh trinh thiet nhung ((cong van) or (cong san)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) sach - hanh trinh thiet nhung ((cong van) OR (cong san)) toan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) OR (hoc thieu)) sach - hanh trinh thiet nhung ((cong van) or (cong san)) toan cau".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) OR (hoc thieu)) sach - hanh trinh thiet nhung ((cong van) or (cong san)) toan cau*.