Perhaps you should try some spelling variations:
san thanh » ban thanh, van thanh, dan thanh
son thanh » ban thanh, van thanh
hieu van » hieu va, thien van, lieu va
tu sach » thu sach, su sach, te sach
van cac » van hac, van cau, van bac
cac dac » cac dan, cac dai, cac bac
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v 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 y nang x hoi. hieu van cac dac ((san thanh) OR (son thanh)) dai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y nang x hoi. hieu van cac dac ((san thanh) OR (son thanh)) dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y nang x hoi. hieu van cac dac ((san thanh) OR (son thanh)) dai cua tre*.