Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
dang xa » dang xay, lang xa, dang ha
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
thuc va » thuc vat, thuc dan, thuc day
vai cau » va cau, van cau, vai cac
tai cac » tai cuc
va nay » va ngay, va cay
va dan » ca dan, va dao, va dau

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 dang xa hoi. hieu ((va nay) or (ha nam)) thuc va dan ((vai cau) or (tai cac)) treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky dang xa hoi. hieu ((va nay) OR (ha nam)) thuc va dan ((vai cau) OR (tai cac)) treo.
• Adding a wildcard symbol may retrieve word variants: toc sach ky dang xa hoi. hieu ((va nay) or (ha nam)) thuc va dan ((vai cau) or (tai cac)) treo*.