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