Perhaps you should try some spelling variations:
co sach » bo sach, cuon sach, hoc sach
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
vai cua » hai cua, lai cua, bai cua
qua ca » qua cac, qua cua, qua cai
vi cua » di cua
x hoi » xa hoi, o hoi, x ho
ca tu » ca tru, cau tu, ca thu

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 ky nang x hoi. hieu qua ca tu va hanh ((vi cua) or (((vai cua) or (dai cua)))) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ky nang x hoi. hieu qua ca tu va hanh ((vi cua) OR (((vai cua) OR (dai cua)))) tre.
• Adding a wildcard symbol may retrieve word variants: co sach ky nang x hoi. hieu qua ca tu va hanh ((vi cua) or (((vai cua) or (dai cua)))) tre*.