Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
cua triet » cua viet, su triet, va triet
nam thuc » nam thuoc, am thuc, nam thu
thuc van » thuc vat, thuc dan, thuc va
thanh di » thanh doi, thanh de, thanh do
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, dua tren
sac ky » cac ky, sai ky
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: su ((sach y) or (sac ky)) nang ma hoa. hieu ve nam thuc van thanh di ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach y) OR (sac ky)) nang ma hoa. hieu ve nam thuc van thanh di ((cua tre) OR (cua triet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach y) or (sac ky)) nang ma hoa. hieu ve nam thuc van thanh di ((cua tre) OR (cua triet))*".