Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
su sach » so sach
dua ban » dia ban, cua ban, mua ban
hai cua » thai cua, dai cua, hoi cua
qua ban » cua ban, qua quan
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
vu sach » vu bach, vu khach
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) OR (vu sach)) y nang xa hoi. hieu va cam ((dua ban) or (qua ban)) thanh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (vu sach)) y nang xa hoi. hieu va cam ((dua ban) OR (qua ban)) thanh hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) OR (vu sach)) y nang xa hoi. hieu va cam ((dua ban) or (qua ban)) thanh hai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) OR (vu sach)) y nang xa hoi. hieu va cam ((dua ban) or (qua ban)) thanh hai cua tre*.