Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
lang van » dang van, tang van, hoang van
thuoc va » thuc va, thuoc ma, thuong va
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach kem
lang xa » lang ha, dang xay
sach ty » sach y, sach tu, sach thu
cuu tre » cua tre, cau tren, cau treo
va nam » van nam, ha nam, va nay
va dan » ca dan, va dao, va dau
dan va » doan va, dan ca, ban va
va cuu » va cau, va chu, va huu

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