Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
tu sach » thu sach, su sach, te sach
va kinh » va tinh, qua kinh
va dinh » van dinh, va tinh, vu dinh
cuc tre » duc tre, cua tre, cuu tre
hieu ve » hieu va, hieu van
nang xa » lang xa, nang ma, mang xa
ve nam » he nam, va nam, le nam

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y ((nang xa) or (nang x)) hoi. hieu ve nam thuoc ((va dinh) OR (va kinh)) tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (nang x)) hoi. hieu ve nam thuoc ((va dinh) OR (va kinh)) tai cuc tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang xa) or (nang x)) hoi. hieu ve nam thuoc ((va dinh) OR (va kinh)) tai cuc tre*".