Perhaps you should try some spelling variations:
so sach » so sanh, bo sach, co sach
sach le » cach le, sach de, sach lo
le xang » le tang, le dang, le quang
xang xa » lang xa, mang xa, ang xa
hieu va » lieu va, hieu qua
va giao » van giao, va giai, va gia
va hanh » van hanh, va thanh, va danh
van anh » van thanh, tuan anh, van minh
vai va » mai va, dai va, hai va
thiet » thieu

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 le xang xa hoi. hieu va giao duc ((va hanh) or (van anh)) vai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach le xang xa hoi. hieu va giao duc ((va hanh) OR (van anh)) vai va thiet.
• Adding a wildcard symbol may retrieve word variants: so sach le xang xa hoi. hieu va giao duc ((va hanh) or (van anh)) vai va thiet*.