Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
ban benh » san benh, ba benh, ban banh
quoc ban » quoc bao, quoc lan, quoc quan
lam quoc » lam duoc, nam quoc, lam thuoc
hoi lang » hoa lang, hoi dan
hoc sach » hoc sinh, hoc cac, hoc anh
lang xa » lang ha, dang xay, lang van
benh va » benh ve, benh dai, benh tai
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
va lam » van lam, va lap

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: ((toc sach) OR (hoc sach)) hoi lang xa hoi. lieu va lam quoc ban benh va ((cua tre) OR (cuu tre))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sach) OR (hoc sach)) hoi lang xa hoi. lieu va lam quoc ban benh va ((cua tre) or (cuu tre))~".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (hoc sach)) hoi lang xa hoi. lieu va lam quoc ban benh va ((cua tre) or (cuu tre))*.