Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
sang tai » hang tai, sang tao, tang tai
sach kem » hanh kem
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
tai hai » thi hai, dai hai, tai ha
hieu ve » hieu van
thuc va » thuc vat, thuc dan, thuc day
hieu va » lieu va, hieu qua
vi cua » vai cua, di cua
cua te » cua tu
sac ky » cac ky, sai ky

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 (sac ky)) sang tai hai. ((hieu ve) OR (hieu va)) tham thuc va danh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach kem) OR (sac ky)) sang tai hai. ((hieu ve) OR (hieu va)) tham thuc va danh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach kem) or (sac ky)) sang tai hai. ((hieu ve) OR (hieu va)) tham thuc va danh vi cua te".
• Adding a wildcard symbol may retrieve word variants: su ((sach kem) or (sac ky)) sang tai hai. ((hieu ve) OR (hieu va)) tham thuc va danh vi cua te*.