Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
thu sach » thuat sach, thuoc sach, thu hoach
hai cua » thai cua, dai cua, hoi cua
dac ban » cac ban, dac san, duc ban
cac dac » cac dan, cac dai, cac bac
van cac » van hac, van cau, van bac
tu sach » su sach, te sach, tu cach
cua tre » cua te, cuu tre, cua triet
v nang » va nang, vu nang, van nang
y nang » ky nang, ly nang, may nang
x hoi » xa hoi, o hoi, x ho

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

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