Perhaps you should try some spelling variations:
theo chieu » theo tieu, theo chu, thi chieu
dung cong » dung trong
ho chieu » hoc thieu, doi chieu, mot chieu
tran xay » tran day, trinh xay, tran xuan
cong ban » cong bang, cong san, cong tan
ban than » ban thanh, van thanh, ban hang
than tap » toan tap, han tap, phan tap
tra xay » thau xay

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