Perhaps you should try some spelling variations:
dang hanh » dang thanh, ban hanh, dang van
thuc dang » thuoc dang, thuc dan, thuc dung
nam thuc » nam thuoc, am thuc, nam thu
sach ty » sach tu, sach thu, xach tay
nang xa » nang x, lang xa, nang ma
hieu ha » hieu hoa, hieu va, hieu ca
tai su » tai so, tai tu, tai du

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