Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam tu
vat dinh » va dinh, van dinh, vat sinh
sach ty » sach y, sach tu, xach tay
lang xa » lang ha, dang xay, lang van
ket cua » ket qua, det cua, keo cua
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: toc ((sach ty) OR (sach thu)) lang xa hoi. hieu van ((nam thuc) OR (nam thu)) vat dinh ket cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ty) or (sach thu)) lang xa hoi. hieu van ((nam thuc) OR (nam thu)) vat dinh ket cua tre~".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ty) or (sach thu)) lang xa hoi. hieu van ((nam thuc) OR (nam thu)) vat dinh ket cua tre*.