Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
tu sach » thu sach, su sach, te sach
van cam » van nam, van lam, van cau
vai cua » dai cua, hai cua, lai cua
thi van » thi lan, thi hanh, thi nang
mai hoi » mai khoi, dai hoi, lai hoi
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang

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 ((y nang) OR (ly nang)) mai hoi. thi van cam ((duc va) or (thuc vat)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((y nang) OR (ly nang)) mai hoi. thi van cam ((duc va) OR (thuc vat)) hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((y nang) OR (ly nang)) mai hoi. thi van cam ((duc va) or (thuc vat)) hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) OR (ly nang)) mai hoi. thi van cam ((duc va) or (thuc vat)) hanh vai cua tre*.