Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
nuoc nam » nuoi nam, nuoc nhat, nguoi nam
ngoc nam » ngoc hai, hoc nam, ngoc ha
dinh lai » dinh lam, dinh lap, dinh tai
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
lai cua » dai cua, hai cua, lai chau
cua tre » cua te, cuu tre, cua triet

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

• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ty ((nang xa) OR (nang ma)) hoi. hieu va cac ((nuoc nam) OR (ngoc nam)) dinh lai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach ty ((nang xa) or (nang ma)) hoi. hieu va cac ((nuoc nam) OR (ngoc nam)) dinh lai cua tre~".
• Adding a wildcard symbol may retrieve word variants: doc sach ty ((nang xa) or (nang ma)) hoi. hieu va cac ((nuoc nam) OR (ngoc nam)) dinh lai cua tre*.