Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
te sach » toc sach
sach ky » sac ky, sach y, sach ty
hieu he » hiem he, hieu le, hieu hien
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc dan, thuc day
va dan » ca dan, va dao, va dau
x hoi » xa hoi, o hoi, x ho
ca tu » cau tu, ca thu, cac tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang x hoi. ((hieu he) OR (hieu ve)) nam thuc va dan ((ca tu) or (ca tru)) tieng~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang x hoi. ((hieu he) OR (hieu ve)) nam thuc va dan ((ca tu) OR (ca tru)) tieng.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang x hoi. ((hieu he) OR (hieu ve)) nam thuc va dan ((ca tu) or (ca tru)) tieng".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang x hoi. ((hieu he) OR (hieu ve)) nam thuc va dan ((ca tu) or (ca tru)) tieng*.