Perhaps you should try some spelling variations:
hieu xuat » hieu suat, chiet xuat, hieu qua
hieu luat » hieu qua
cua viet » ca viet, hoa viet, cua vat
dao hang » dao khang, dao hanh, dat hang
sach dao » lanh dao
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
xay duc » xa duc, xay dung, xuan duc
te sach » toc sach
va hoa » van hoa, va hoc, ma hoa
va hoi » xa hoi, va hoc
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach dao hang ((va hoi) or (va hoa)). ((hieu xuat) or (hieu luat)) xay duc va hanh va cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach dao hang ((va hoi) OR (va hoa)). ((hieu xuat) OR (hieu luat)) xay duc va hanh va cua viet.
• Adding a wildcard symbol may retrieve word variants: te sach dao hang ((va hoi) or (va hoa)). ((hieu xuat) or (hieu luat)) xay duc va hanh va cua viet*.