Perhaps you should try some spelling variations:
cac thuc » cach thuc, cac thu, can thuc
thanh vi » thanh va, thanh ve, nhanh vi
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
cua tre » cua te, cuu tre, cua triet
so sac » so sach, so dac
sac ky » cac ky, sai ky
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sac ky nang ((x hoi) or (xa hoi)). hieu va cac thuc va ((thanh vi) or (hanh vi)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sac ky nang ((x hoi) OR (xa hoi)). hieu va cac thuc va ((thanh vi) OR (hanh vi)) cua tre.
• Adding a wildcard symbol may retrieve word variants: so sac ky nang ((x hoi) or (xa hoi)). hieu va cac thuc va ((thanh vi) or (hanh vi)) cua tre*.