Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
cua viet » ca viet, hoa viet, cua vat
thanh vi » hanh vi, thanh va, thanh ve
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
su hien » su kien, su tien, thu hien
hoa hoi » khoa hoi, hoa hoc, hoa doi
cam tu » cam thu, nam tu, dam tu
tu ban » thu ban, te ban
ha hoi » ha noi, xa hoi, va hoi
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach _ lang ((ha hoi) or (hoa hoi)). hieu va cam tu ban thanh vi ((cua viet) or (su hien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach _ lang ((ha hoi) OR (hoa hoi)). hieu va cam tu ban thanh vi ((cua viet) OR (su hien)).
• Adding a wildcard symbol may retrieve word variants: su sach _ lang ((ha hoi) or (hoa hoi)). hieu va cam tu ban thanh vi ((cua viet) or (su hien))*.