Perhaps you should try some spelling variations:
cau thuc » cau truc, cuu thuc, can thuc
vat hanh » vat thanh, van hanh, va hanh
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
qua cau » quan cau, qua cac, qua ca
sai ky » sac ky
va cua » va chua, via cua, ma cua
ca cua » co cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ty) or (sai ky)) nang xa hoi. hieu qua cau thuc vat hanh ((va cua) or (ca cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sai ky)) nang xa hoi. hieu qua cau thuc vat hanh ((va cua) OR (ca cua)) triet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sai ky)) nang xa hoi. hieu qua cau thuc vat hanh ((va cua) or (ca cua)) triet*.