Perhaps you should try some spelling variations:
ve triet » va trien
su triet » su viet, su tien
nam thuc » nam thuoc, am thuc, nam thu
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
qua nam » quan nam, cua nam, quang nam
sach ky » sac ky, sach y, sach kem
thuc va » thuc vat, thuc dan, thuc day
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va

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 ky) or (sach ty)) nang xa hoi. hieu qua nam thuc va dan vi ((su triet) or (ve triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach ty)) nang xa hoi. hieu qua nam thuc va dan vi ((su triet) OR (ve triet)).
• Adding a wildcard symbol may retrieve word variants: su ((sach ky) or (sach ty)) nang xa hoi. hieu qua nam thuc va dan vi ((su triet) or (ve triet))*.