Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
vai cuu » vai cua
dao vai » dao van, dao va, dao bai
thuc va » thuc vat, thuc dan, thuc day
sach ky » sac ky, sach y, sach ty
cuu tre » cua tre, cau tren, cau treo
lang xa » lang ha, dang xay, lang van
tang xa » trang xa, tang ma, tang ha
va nay » va ngay, va cay
va dao » ca dao
va nam » van nam, ha nam

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky ((tang xa) OR (lang xa)) hoi. hieu ((va nam) or (va nay)) thuc va dao vai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky ((tang xa) OR (lang xa)) hoi. hieu ((va nam) OR (va nay)) thuc va dao vai cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky ((tang xa) OR (lang xa)) hoi. hieu ((va nam) or (va nay)) thuc va dao vai cuu tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ky ((tang xa) OR (lang xa)) hoi. hieu ((va nam) or (va nay)) thuc va dao vai cuu tre*.