Does Speed Count in Searching Room & Finding Items

To be lucky to find things while searching a room, are you to spend the least time by quickly finding the items on the list, or use up the majority of the time allotted and find all of the objects?

I've tried both ploys and still have a lot of times where it tells me I was not lucky to find anything.

My guess is that room search completion time does not affect whether or not you find any item.