Perhaps you should try some spelling variations:
sach thue » sach thieu, sach tham, cach thuc
hanh vai » hanh vi, hanh va, hanh tai
sach thu » sach thieu, sach tham, cach thuc
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
va cam » va cham, va cac, va cao
x hoi » xa hoi, o hoi, x ho

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

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