Perhaps you should try some spelling variations:
so sach » so sanh, bo sach, co sach
va hanh » van hanh, va thanh, ban hanh
doi cua » dai cua, hoi cua
va danh » va dinh, va dan, dia danh
va nang » van nang, da nang, cam nang
hieu ve » hieu va, hieu van
cac tuc » cac toc, cac tu, cac tac
ve cac » va cac, vien cac
v nang » vu nang, van nang, voi nang
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: so sach ((v nang) OR (va nang)) xa hoi. hieu ve cac tuc ((va hanh) or (va danh)) doi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((v nang) OR (va nang)) xa hoi. hieu ve cac tuc ((va hanh) OR (va danh)) doi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((v nang) OR (va nang)) xa hoi. hieu ve cac tuc ((va hanh) or (va danh)) doi cua te".
• Adding a wildcard symbol may retrieve word variants: so sach ((v nang) OR (va nang)) xa hoi. hieu ve cac tuc ((va hanh) or (va danh)) doi cua te*.