Perhaps you should try some spelling variations:
day nhanh » day thanh, duy nhanh, dac nhan
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
day hanh » day thanh, day manh, da hanh
dao hanh » dao thanh, dang hanh, ban hanh
cua tre » cua te, cuu tre, cua triet
vu san » va san, vu ban
san ky » sang ky, van ky, dan ky
di cua » dai cua, doi cua, de 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: vu san ky nang x hoi. hieu van nam thuc ((((day hanh) or (dao hanh))) or (day nhanh)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu san ky nang x hoi. hieu van nam thuc ((((day hanh) OR (dao hanh))) OR (day nhanh)) di cua tre.
• Adding a wildcard symbol may retrieve word variants: vu san ky nang x hoi. hieu van nam thuc ((((day hanh) or (dao hanh))) or (day nhanh)) di cua tre*.