Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
vat hanh » vat thanh, van hanh, va hanh
tu sach » thu sach, su sach, te sach
vu kham » vu khanh
vai cua » dai cua, hai cua, lai cua
hoc vat » hoc va, hoc viet, thuc vat
cua tre » cua te, cuu tre, cua triet
vu cham » va cham, tu cham, qua cham
ty ang » ty hang, ty anh

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 ang) OR (ty xang)) xa hoi. hieu ((vu cham) or (vu kham)) hoc vat hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty ang) OR (ty xang)) xa hoi. hieu ((vu cham) OR (vu kham)) hoc vat hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty ang) OR (ty xang)) xa hoi. hieu ((vu cham) or (vu kham)) hoc vat hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty ang) OR (ty xang)) xa hoi. hieu ((vu cham) or (vu kham)) hoc vat hanh vai cua tre*.