Perhaps you should try some spelling variations:
thuc van » thuc vat, thuc va, thuc hanh
thanh di » thanh doi, thanh de, thanh do
thuc dan » thuc hanh, hoc dan, thuc vat
nang ma » tang ma, sang ma, nang cao
hieu he » hieu ve, hiem he, hieu le
di cua » dai cua, doi cua, de cua
he nam » ha nam, nghe nam
ma hoi » mai hoi, xa hoi, ma hoa
sac ky » cac ky, sai ky
cua te » cua tu

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 hoi. hieu he nam ((thuc van) OR (thuc dan)) thanh di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach y) OR (sac ky)) nang ma hoi. hieu he nam ((thuc van) OR (thuc dan)) thanh di cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach y) or (sac ky)) nang ma hoi. hieu he nam ((thuc van) OR (thuc dan)) thanh di cua te".
• Adding a wildcard symbol may retrieve word variants: su ((sach y) or (sac ky)) nang ma hoi. hieu he nam ((thuc van) OR (thuc dan)) thanh di cua te*.