Perhaps you should try some spelling variations:
nuoc sach » nguoi sach, cuoc cach, cuon sach
hoc sach » hoc sinh, hoc cac, hoc anh
hanh vai » hanh vi, hanh va, hanh tai
vai cua » dai cua, hai cua, lai cua
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc sach) or (nuoc sach)) ky lang xa hoi. hieu va cam ((xuc va) OR (luc va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (nuoc sach)) ky lang xa hoi. hieu va cam ((xuc va) OR (luc va)) hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc sach) or (nuoc sach)) ky lang xa hoi. hieu va cam ((xuc va) OR (luc va)) hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((hoc sach) or (nuoc sach)) ky lang xa hoi. hieu va cam ((xuc va) OR (luc va)) hanh vai cua tre*.