Perhaps you should try some spelling variations:
cach van » cac van, bach van, canh van
cac thuc » cach thuc, cac thu, can thuc
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
sach va » sach xa, sach ha, sach dao
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
vi su » va su, ve su, oi su
ki su » ky 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 ((cach van) or (sach va)) nang xa hoi. hieu va cac thuc van hanh ((vi su) OR (ki su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((cach van) OR (sach va)) nang xa hoi. hieu va cac thuc van hanh ((vi su) OR (ki su)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((cach van) or (sach va)) nang xa hoi. hieu va cac thuc van hanh ((vi su) OR (ki su)) triet".
• Adding a wildcard symbol may retrieve word variants: su ((cach van) or (sach va)) nang xa hoi. hieu va cac thuc van hanh ((vi su) OR (ki su)) triet*.