Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
toc sach » hoc sach, doc sach, nuoc sach
ban benh » san benh, ba benh, ban banh
quoc ban » quoc bao, quoc lan, quoc quan
va chat » van chat, va phat, cao chat
benh vi » benh va, benh ve, benh li
cuu tre » cua tre, cau tren, cau treo
va cham » va tham
lang xa » lang ha, dang xay, lang van
y lang » o lang, _ lang, tay lang
vi cuu » vi luu, vinh cuu

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) or (thuoc sach)) y lang xa hoi. hieu ((va cham) or (va chat)) quoc ban benh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sach) OR (thuoc sach)) y lang xa hoi. hieu ((va cham) OR (va chat)) quoc ban benh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((toc sach) or (thuoc sach)) y lang xa hoi. hieu ((va cham) or (va chat)) quoc ban benh vi cuu tre*.