Touch everything
Explanation based on my own experience:
I can’t find something. It’s literally right in front of me, but there is a mix of things and I JUST DON’T SEE IT. Grr.
I start on one side and start touch everything one at a time until it somehow magically appears. It was there the whole time.
If I sense that this type of thing is happening and I’m looking only visually, it’s not there. It’s just not there.
Touch works better than eyes.
I will try to envision me using that object, and mime putting it down when I’m done with it. Sometimes that’s enough to trigger the memory of where I left it.