Friends research privacy

Hi guys! I have a simple question:

Recently a friend of mine on Facebook, told me that he saw on his notification wall - (news feed tab), a suggested notification which was inviting him to connect with another unknown user related to one of my private friends research. The post was inviting him to connect to this user, according to the fact that I (me) was searching about that user on my private searching history, even if I have never became a friend of this user. How could have he seen it?

Let me try to explain dropping 3 random names:

"Maria" was searching for "Greg", privately, and never ask for FB friendship to him. Then "John" (Maria's friend) received a notification to became friend to "Greg" (with whom "John" doesn’t have any common friends), in which notification Facebook would suggest "Greg" to "John", since "Maria" was previously searching for "Greg", and so "John" may find "Greg" interesting. Is that possible???

To me, it sounds pretty weird and looks more like that "John" could’ve secretly logged into "Maria" 's Facebook, and seen her search history.

I would appreciate to have your technical support about it guys, cause is important to me to understand if this person logged into my account.

Thanks in advance Guys!!


Have a wonderful week!

 

I forgot to say that "Maria" searched "Greg" for real, but never asked neither became friend with him. (standing with random names)