Perhaps you should try some spelling variations:
day nhanh » day thanh, duy nhanh, dac nhan
cam thuc » am thuc, nam thuc, cam thu
thuc day » thuc dan, thuc vat
su sach » so sach, vu sach
hieu ve » hieu van
hieu va » lieu va, hieu qua
y nang » ky nang, ly nang, v nang
di cua » doi cua, de cua, do cua
x hoi » xa hoi, o hoi, x ho

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 y nang x hoi. ((hieu ve) or (hieu va)) cam thuc day nhanh ((di cua) OR (dai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang x hoi. ((hieu ve) OR (hieu va)) cam thuc day nhanh ((di cua) OR (dai cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang x hoi. ((hieu ve) or (hieu va)) cam thuc day nhanh ((di cua) OR (dai cua)) triet".
• Adding a wildcard symbol may retrieve word variants: su sach y nang x hoi. ((hieu ve) or (hieu va)) cam thuc day nhanh ((di cua) OR (dai cua)) triet*.