Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
thuc va » thuc vat, thuc dan, thuc day
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
cua tre » cua te, cuu tre, cua triet
va lam » van lam, va lap
xuc va » duc va, tuc va, luc va
o hoi » co hoi, o hoc, o hai
x hoi » xa 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: tu sach ty nang ((x hoi) OR (o hoi)). lieu va lam ((xuc va) or (thuc va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty nang ((x hoi) OR (o hoi)). lieu va lam ((xuc va) OR (thuc va)) hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang ((x hoi) OR (o hoi)). lieu va lam ((xuc va) or (thuc va)) hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang ((x hoi) OR (o hoi)). lieu va lam ((xuc va) or (thuc va)) hanh vai cua tre*.