Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach tri » sach tai, sach tren, sach truc
hieu van » hieu va, thien van, lieu va
cac ban » cac dan, cac van, can ban
cuc ban » cua ban, cuu ban, duc ban
van lam » van nam
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang 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: thu sach tri ((nang xa) OR (lang xa)) hoi. hieu van lam ((cuc ban) OR (cac ban)) hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach tri ((nang xa) or (lang xa)) hoi. hieu van lam ((cuc ban) OR (cac ban)) hanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: thu sach tri ((nang xa) or (lang xa)) hoi. hieu van lam ((cuc ban) OR (cac ban)) hanh vi cua tre*.