Perhaps you should try some spelling variations:
nam thuoc » nam thu, nha thuoc, cay thuoc
nam thuc » am thuc, nam thu, nam tu
toc sach » hoc sach, doc sach, thuoc sach
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
dan tai » van tai, dan thi, ban tai
han tai » hang tai, nhan tai, van tai
cuu tre » cua tre, cau tren, cau treo

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 ky lang xa hoi. hieu va ((nam thuc) OR (nam thuoc)) va ((dan tai) OR (han tai)) cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky lang xa hoi. hieu va ((nam thuc) or (nam thuoc)) va ((dan tai) OR (han tai)) cuu tre~".
• Adding a wildcard symbol may retrieve word variants: toc sach ky lang xa hoi. hieu va ((nam thuc) or (nam thuoc)) va ((dan tai) OR (han tai)) cuu tre*.