Perhaps you should try some spelling variations:
thieu tach » thien hach, chieu sach, hieu cach
chiet tach » chieu sach
hanh trinh » canh tranh, hanh chinh
nhung dung » phuong dung, ung dung, thong dung
trinh cua » tinh cua, trinh luat, trinh quan
cua nhung » va nhung
van toan » van tan, van thanh, manh toan
van tuan » van quan, van ban, anh tuan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu tach) OR (chiet tach)) - hanh trinh cua nhung dung ((van toan) or (van tuan)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu tach) OR (chiet tach)) - hanh trinh cua nhung dung ((van toan) OR (van tuan)) ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu tach) OR (chiet tach)) - hanh trinh cua nhung dung ((van toan) or (van tuan)) ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu tach) OR (chiet tach)) - hanh trinh cua nhung dung ((van toan) or (van tuan)) ban*.