Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
te sach » toc sach
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va danh, ban hanh
cua tre » cua te, cuu tre, cua triet
tu nang » tru nang, tu nong, tu nano
hieu vo » hieu voi, hieu va, hieu ve
co tuc » co thuc, co tu, co toc
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: te sach ((tu nang) or (truc nano)) x hoi. hieu vo co tuc ((va hanh) OR (va thanh)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((tu nang) OR (truc nano)) x hoi. hieu vo co tuc ((va hanh) OR (va thanh)) vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((tu nang) or (truc nano)) x hoi. hieu vo co tuc ((va hanh) OR (va thanh)) vai cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ((tu nang) or (truc nano)) x hoi. hieu vo co tuc ((va hanh) OR (va thanh)) vai cua tre*.