Perhaps you should try some spelling variations:
day nhanh » day thanh, duy nhanh, dac nhan
cam thuc » am thuc, nam thuc, cam thu
day hanh » day thanh, dao hanh, day manh
sach ky » sac ky, sach ty, sach kem
doi cua » dai cua, hoi cua
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
cua te » cua tu
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: vu ((sach ky) OR (sach y)) nang x hoi. hieu ve cam thuc ((day hanh) or (day nhanh)) doi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((sach ky) OR (sach y)) nang x hoi. hieu ve cam thuc ((day hanh) OR (day nhanh)) doi cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ((sach ky) OR (sach y)) nang x hoi. hieu ve cam thuc ((day hanh) or (day nhanh)) doi cua te*".