Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
doc sach » hoc sach, toc sach, nuoc sach
thuoc va » thuc va, thuoc ma, thuong va
vai cuu » vai cua
dan vai » dan va, dan tai, dan vat
sach ky » sac ky, sach y, sach ty
cuu tre » cua tre, cau tren, cau treo
hieu va » hieu qua
lang xa » lang ha, dang xay, lang van
va dan » ca dan, va dao, va dau

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

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