Perhaps you should try some spelling variations:
ban hanh » ban hang
tu sach » thu sach, su sach, te sach
vai cuu » vai cua
va dinh » van dinh, va kinh, va tinh
cao duc » dao duc, cao suc, giao duc
hang xa » hoang xa, hang ca, lang xa
hieu ve » hieu va, hieu van
cuu tre » cua tre, cau tren, cau treo
ve cao » va cao, ve bao, ve cac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y ((hang xa) or (hang va)) hoi. hieu ve cao duc ((ban hanh) or (va dinh)) vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((hang xa) OR (hang va)) hoi. hieu ve cao duc ((ban hanh) OR (va dinh)) vai cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu sach y ((hang xa) or (hang va)) hoi. hieu ve cao duc ((ban hanh) or (va dinh)) vai cuu tre*.