Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
van thanh » ban thanh, van tuan
hieu van » hieu va, thien van, lieu va
te sach » toc sach
cau luc » cau truc, cau phuc
cam luc » cam xuc
sang ma » nang ma, sang tao, mang may
tang ma » mang may, tang van
cua tre » cua te, cuu tre, cua triet

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach _ ((sang ma) OR (tang ma)) hoi. hieu van ((cam luc) OR (cau luc)) van thanh dai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach _ ((sang ma) or (tang ma)) hoi. hieu van ((cam luc) OR (cau luc)) van thanh dai cua tre~".
• Adding a wildcard symbol may retrieve word variants: te sach _ ((sang ma) or (tang ma)) hoi. hieu van ((cam luc) OR (cau luc)) van thanh dai cua tre*.