Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
va thanh » gia thanh, ban thanh, le thanh
hieu van » hieu va, thien van, lieu va
dai cuu » dai cua, dai huu
va tinh » may tinh
nam tuc » nam thuc, nam truc, nam tu
te sach » toc sach
cuu tre » cua tre, cau tren, cau treo
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: ((thu sach) or (te sach)) ky nang x hoi. hieu van nam tuc ((va thanh) OR (va tinh)) dai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (te sach)) ky nang x hoi. hieu van nam tuc ((va thanh) OR (va tinh)) dai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (te sach)) ky nang x hoi. hieu van nam tuc ((va thanh) OR (va tinh)) dai cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (te sach)) ky nang x hoi. hieu van nam tuc ((va thanh) OR (va tinh)) dai cuu tre*.