This question already has an answer here:
The room of requirement is supposed to fulfill the seeker's needs. Voldemort needed to hide his Hocrux where none could reach. Now how come Harry Potter could find the Hocrux hidden in the room of requirement?. Is the magic of the room limited to time?
Suppose someone says I need a place to hide where none could reach before hiding. If another person enters the room and after saying I need that particular thing to be found. What would happen then ?