Perhaps you should try some spelling variations:
doc sach » toc sach, nuoc sach, dac sac
hoc sach » hoc sinh, hoc cac, hoc anh
hanh lai » hanh lam, hanh tai, thanh lap
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
xuc va » duc va, luc va, xac 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: ((doc sach) OR (hoc sach)) ky nang x hoi. hieu va cam ((xuc va) OR (tuc va)) hanh lai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc sach) OR (hoc sach)) ky nang x hoi. hieu va cam ((xuc va) OR (tuc va)) hanh lai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((doc sach) OR (hoc sach)) ky nang x hoi. hieu va cam ((xuc va) OR (tuc va)) hanh lai cua tre*.