Perhaps you should try some spelling variations:
va doanh » van doanh, vay doanh, va danh
co sach » bo sach, cuon sach, hoc sach
ty nang » ky nang, ty xang, ly nang
ty hang » ly hang, ty xang, thi hang
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
dan cua » ban cua, dai cua, day cua
x hoi » xa hoi, o hoi, x ho

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 ((ty nang) or (ty hang)) x hoi. hieu ve pham duc va doanh ((dan cua) OR (dan ca)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach ((ty nang) OR (ty hang)) x hoi. hieu ve pham duc va doanh ((dan cua) OR (dan ca)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach ((ty nang) or (ty hang)) x hoi. hieu ve pham duc va doanh ((dan cua) OR (dan ca)) te".
• Adding a wildcard symbol may retrieve word variants: co sach ((ty nang) or (ty hang)) x hoi. hieu ve pham duc va doanh ((dan cua) OR (dan ca)) te*.