Perhaps you should try some spelling variations:
nam thuoc » nam thu, nha thuoc, cay thuoc
nam thuc » am thuc, nam thu, nam tu
toc sac » toc sach, toc san, hoc sach
van tai » von tai, van tuan
dan vai » dan va, dan tai, dan vat
cuu tre » cua tre, cau tren, cau treo
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
sac ky » cac ky, sai ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sac ky lang xa hoi. hieu va ((nam thuc) OR (nam thuoc)) va ((dan vai) or (van tai)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sac ky lang xa hoi. hieu va ((nam thuc) OR (nam thuoc)) va ((dan vai) OR (van tai)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sac ky lang xa hoi. hieu va ((nam thuc) OR (nam thuoc)) va ((dan vai) or (van tai)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: toc sac ky lang xa hoi. hieu va ((nam thuc) OR (nam thuoc)) va ((dan vai) or (van tai)) cuu tre*.