Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
hanh tai » thanh tai, hang tai, han tai
su triet » su viet, su tien, ve triet
nang xa » nang x, lang xa, nang ma
hieu ha » hieu hoa, hieu va, hieu ca
tai su » tai so, tai tu, lai su

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 kem) OR (hanh kem))) or (sach y)) nang xa hoi. hieu ha nam thuc dan hanh tai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((((sach kem) OR (hanh kem))) OR (sach y)) nang xa hoi. hieu ha nam thuc dan hanh tai su triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((((sach kem) OR (hanh kem))) or (sach y)) nang xa hoi. hieu ha nam thuc dan hanh tai su triet*".