Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
van hanh » ban hanh, van anh, van ban
chau tre » chay tren, chau tho, cho tre
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
van cam » van nam, van lam, van cau

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 ky ((nang ma) or (sang ma)) hoi. hieu van cam xuc ((van hanh) or (van thanh)) lai chau tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky ((nang ma) OR (sang ma)) hoi. hieu van cam xuc ((van hanh) OR (van thanh)) lai chau tre.
• Adding a wildcard symbol may retrieve word variants: thu sach ky ((nang ma) or (sang ma)) hoi. hieu van cam xuc ((van hanh) or (van thanh)) lai chau tre*.