Perhaps you should try some spelling variations:
co sach » bo sach, cuon sach, hoc sach
ve pham » v pham, ve phan, ve phat
va danh » va dinh, va dan, dia danh
va hanh » van hanh, va thanh, ban hanh
vai cua » dai cua, hai cua, lai cua
y nang » ky nang, ly nang, v nang
nang o » nang co, nang ho, nang ro
cua te » cua tu
o hoi » co hoi, o hoc, o hai

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 y nang o hoi. hieu ((ve pham) OR (vi 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 y nang o hoi. hieu ((ve pham) OR (vi 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 y nang o hoi. hieu ((ve pham) OR (vi pham)) duc ((va danh) or (va hanh)) vai cua te".
• Adding a wildcard symbol may retrieve word variants: co sach y nang o hoi. hieu ((ve pham) OR (vi pham)) duc ((va danh) or (va hanh)) vai cua te*.