Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
van thanh » ban thanh, van tuan
va triet » va thiet, va trien, ve triet
sach ky » sac ky, sach y, sach ty
cam duc » cam xuc, cao duc, nam duoc
tu sach » thu sach, su sach, te sach
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
vai va » mai va, dai va, hai va

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 ky ((nang ma) or (nang x)) hoi. hieu ve ((cam duc) or (pham duc)) van thanh vai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang ma) OR (nang x)) hoi. hieu ve ((cam duc) OR (pham duc)) van thanh vai va triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang ma) or (nang x)) hoi. hieu ve ((cam duc) or (pham duc)) van thanh vai va triet*.