Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
thanh va » thanh van, hanh va, thanh ha
dang mam » dang nam, dang mau, dang mat
thuc va » thuc dan, thuc day
sach ky » sac ky, sach y, sach ty
te sach » toc sach
dang ma » dang mau, dang mat, tang ma
hieu ve » hieu va, hieu van
ve nam » he nam, va nam, le nam
va cau » van cau, va cac, va dau

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((dang ma) OR (dang mam)) hoi. hieu ve nam ((thuc va) OR (thuc vat)) thanh va cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((dang ma) or (dang mam)) hoi. hieu ve nam ((thuc va) OR (thuc vat)) thanh va cau tren~".
• Adding a wildcard symbol may retrieve word variants: te sach ky ((dang ma) or (dang mam)) hoi. hieu ve nam ((thuc va) OR (thuc vat)) thanh va cau tren*.