Perhaps you should try some spelling variations:
hoac khong » hoa khong, hoc khong, hay khong
tang thanh » dang thanh, trung thanh, hoang thanh
hoc thieu » toc thieu, hoc hien
hua khong » hoa khong, cua khong, phuc khong
cong tang » cong thang, cong tan, cong lang
thanh cac » hanh cac, thanh bac, thanh ca
ho chieu » theo chieu, doi chieu, mot chieu

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 - canh tranh ((hua khong) OR (hoac khong)) cong tang thanh cac~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((ho chieu) OR (hoc thieu)) sach - canh tranh ((hua khong) OR (hoac khong)) cong tang thanh cac.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((ho chieu) or (hoc thieu)) sach - canh tranh ((hua khong) OR (hoac khong)) cong tang thanh cac".
• Adding a wildcard symbol may retrieve word variants: ((ho chieu) or (hoc thieu)) sach - canh tranh ((hua khong) OR (hoac khong)) cong tang thanh cac*.