But to retrieve the document you would have to go in my drawer?
Not the same at all.
Maybe if the draw was outside and there was a camera showing inside of the draw and if anyone could travel at the speed of light. Still not the same at all.
You are leaking more information online than you realize. If your contact viewed that in chrome, google may have already visited the unlinked document.
Google is really interested in indexing anything it doesn't know.
It is the same. If I'd like to share a draft letter with someone over IRC's DM or some internal IRC channel, I'd upload it to my HTTP server's "stuff" folder with file listing disabled and paste the link.
Why would I use a browser that sends what I browse to some third parties and index those things in the first place?
I mean, I know that this is a common thing these days, but it didn't use to be for a very long time. And it's still not what happens on my PC or phone.