Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thanh vi » hanh vi, thanh va, thanh ve
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
nam tu » nam thu, nam thuc
tu gia » tu giao, tu giac, tu giay

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 ky nang ((co hoc) or (xa hoi)). hieu van nam tu gia thanh vi ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang ((co hoc) OR (xa hoi)). hieu van nam tu gia thanh vi ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((co hoc) or (xa hoi)). hieu van nam tu gia thanh vi ((cua tre) or (cuu tre))*.