Perhaps you should try some spelling variations:
cau quoc » cac quoc, cao quoc, han quoc
toc sach » hoc sach, doc sach, thuoc sach
benh te » benh tre, benh ve, benh he
lang xa » lang ha, dang xay, lang van
hieu va » hieu qua
bo benh » so benh, o benh, ba benh
quoc bo » quoc bao, nuoc bo, quoc co
te cua » tue cua, le cua, de cua
cua te » cua tu
y lang » o lang, _ lang, tay lang

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