Perhaps you should try some spelling variations:
dang thanh » dong thanh, dang hanh, hoang thanh
nhung cong » thong cong, nhung don, nhung lang
hieu cach » hieu cac, chieu sach, hieu ca
tranh cua » doanh cua, manh cua
hang cong » dang cong, hang nong, bang cong
dung cong » dung trong
thanh cau » thanh chau, thanh mau, nhanh cau
hoc hieu » hoc thieu, hoc hien, doc hieu

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hieu cach - canh tranh cua ((((nhung cong) OR (hang cong))) OR (dung cong)) dang thanh cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hieu cach - canh tranh cua ((((nhung cong) OR (hang cong))) or (dung cong)) dang thanh cau~".
• Adding a wildcard symbol may retrieve word variants: hoc hieu cach - canh tranh cua ((((nhung cong) OR (hang cong))) or (dung cong)) dang thanh cau*.