Perhaps you should try some spelling variations:
day nhanh » day thanh, duy nhanh, dac nhan
cam thuc » nam thuc, cam thu, can thuc
ban hanh » ban hang
vu sach » vu bach, su sach, vu khach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
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 ty nang x hoi. hieu va ((cam thuc) or (am thuc)) ((ban hanh) or (day nhanh)) dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty nang x hoi. hieu va ((cam thuc) OR (am thuc)) ((ban hanh) OR (day nhanh)) dai cua tre.
• Adding a wildcard symbol may retrieve word variants: vu sach ty nang x hoi. hieu va ((cam thuc) or (am thuc)) ((ban hanh) or (day nhanh)) dai cua tre*.