Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
day thanh » dao thanh, dat thanh, da thanh
day manh » van manh, duc manh, ha manh
cua tre » cua te, cuu tre, cua triet
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
sac ky » cac ky, sai ky
di cua » dai cua, doi cua, de cua
vu sac » vu sach, vu san, va sac
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: vu sac ky nang ((x hoi) or (o hoi)). hieu ve cham thuc ((day thanh) or (day manh)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sac ky nang ((x hoi) OR (o hoi)). hieu ve cham thuc ((day thanh) OR (day manh)) di cua tre.
• Adding a wildcard symbol may retrieve word variants: vu sac ky nang ((x hoi) or (o hoi)). hieu ve cham thuc ((day thanh) or (day manh)) di cua tre*.