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
doi cua » dai cua, hoi cua
vu sach » vu bach, su sach, vu khach
hieu va » lieu va, hieu qua
so sach » so sanh, bo sach, co sach
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
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) or (so sach)) ky nang x hoi. hieu va cam thuc ((day hanh) or (day nhanh)) doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (so sach)) ky nang x hoi. hieu va cam thuc ((day hanh) OR (day nhanh)) doi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((vu sach) or (so sach)) ky nang x hoi. hieu va cam thuc ((day hanh) or (day nhanh)) doi cua tre*.