Perhaps you should try some spelling variations:
nam thuc » nam thuoc, nam thu, nam tu
danh dai » danh dau, danh di, danh sai
huu them » huu thu, huu thuc, huu liem
tu sach » thu sach, su sach, te sach
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu he » hieu ve, hiem he, hieu le
xa danh » va danh, dia danh, nam danh
dai huu » dao huu, dai hau, dai thua

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 (lang xa)) hoi. hieu he ((nam thuc) OR (am thuc)) xa danh dai huu them~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (lang xa)) hoi. hieu he ((nam thuc) OR (am thuc)) xa danh dai huu them.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y ((nang xa) or (lang xa)) hoi. hieu he ((nam thuc) OR (am thuc)) xa danh dai huu them".
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang xa) or (lang xa)) hoi. hieu he ((nam thuc) OR (am thuc)) xa danh dai huu them*.