Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hai cua » thai cua, dai cua, hoi cua
dua ban » dia ban, cua ban, qua ban
duc ban » duc tan, duc van, duc man
tang xa » trang xa, tang ma, lang xa
hieu ve » hieu va, hieu van
ky tang » ky nang, ky dang, kho tang
cua tre » cua te, cuu tre, cua triet
hieu v » hieu va, hieu 2, hieu _

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 ky tang xa hoi. ((hieu v) OR (hieu ve)) pham ((duc ban) OR (dua ban)) thanh hai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky tang xa hoi. ((hieu v) or (hieu ve)) pham ((duc ban) OR (dua ban)) thanh hai cua tre~".
• Adding a wildcard symbol may retrieve word variants: su sach ky tang xa hoi. ((hieu v) or (hieu ve)) pham ((duc ban) OR (dua ban)) thanh hai cua tre*.