Perhaps you should try some spelling variations:
sach thue » sach thieu, sach tham, cach thuc
hieu van » hieu va, thien van, lieu va
sach thu » sach thieu, sach tham, cach thuc
cap nuoc » dat nuoc
va hanh » van hanh, va thanh, va danh
cac xuc » cam xuc, cac nuoc, chat xuc
xang xa » lang xa, mang xa, ang xa
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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: su ((sach thu) OR (sach thue)) xang xa hoi. hieu van ((cac xuc) OR (cap nuoc)) va hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach thu) OR (sach thue)) xang xa hoi. hieu van ((cac xuc) or (cap nuoc)) va hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: su ((sach thu) OR (sach thue)) xang xa hoi. hieu van ((cac xuc) or (cap nuoc)) va hanh vi cua tre*.