How to find and retrieve a bluetooth pdf file on my lumia?

So, my friend bluetoothed a fairly large pdf file to my lumia (around 70 mb). Now, the problem is, I can find the document under 'recent' in my phone's pdf reader (Adobe Reader), owever, I cannot for the life of me find the file anywhere else, even when i perform a search for it through the phone and through my pc.

It just seems to have vanished from everywhere else.

Keep in mind that my other pdf documents and files I can find easily, just this one that is giving me trouble.

So my question is, how do I find this file and get it on my pc?

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