Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
co sach » bo sach, cuon sach
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
va danh » va dinh, va dan, dia danh
va hanh » van hanh, va thanh, ban hanh
vai cua » dai cua, hai cua, lai cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((co sach) OR (hoc sach)) ky nang x ho. hieu ve pham duc ((va danh) or (va hanh)) vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((co sach) OR (hoc sach)) ky nang x ho. hieu ve pham duc ((va danh) OR (va hanh)) vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((co sach) OR (hoc sach)) ky nang x ho. hieu ve pham duc ((va danh) or (va hanh)) vai cua te".
• Adding a wildcard symbol may retrieve word variants: ((co sach) OR (hoc sach)) ky nang x ho. hieu ve pham duc ((va danh) or (va hanh)) vai cua te*.