Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
sach ky » sac ky, sach y, sach ty
vai cua » dai cua, hai cua, lai cua
hieu ve » hieu va, hieu van
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
mang xa » lang xa, mang may, dang xay
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam
xuc va » tuc va, luc va, xac va

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 ky ((mang xa) or (nang ma)) hoi. hieu ve cam ((xuc va) OR (duc va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((mang xa) OR (nang ma)) hoi. hieu ve cam ((xuc va) OR (duc va)) hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((mang xa) or (nang ma)) hoi. hieu ve cam ((xuc va) OR (duc va)) hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((mang xa) or (nang ma)) hoi. hieu ve cam ((xuc va) OR (duc va)) hanh vai cua tre*.