Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van pham » san pham, van phan, van phat
va thanh » gia thanh, ban thanh, va tinh
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
va pham » va phat, va phap, va phan
va hanh » van hanh, va danh, ban hanh
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang ma hoi. hieu ((va pham) OR (van pham)) duc ((va hanh) or (va thanh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang ma hoi. hieu ((va pham) OR (van pham)) duc ((va hanh) OR (va thanh)) dai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang ma hoi. hieu ((va pham) OR (van pham)) duc ((va hanh) or (va thanh)) dai cua tre*".