I think the best place to hide something from someone is with them. They'd search you and your stuff but would never ever think to search themselves.

Take for example a case where an evil society is planning a putsch and you happen to have their ultimate weapon then they want it from you, you could hide it in the house of one of them, maybe bury it in their yard, give it to a family member as a gift or even have it sent, disguised, to the organization. They'd stalk you, stalk your family, torture, harm, you name it, but they'd never think to check themselves.

It may not work if the object of attention happens to have a tracker on it. 🙃

It's crazy, right? 😆