I think maybe people who read these questions and answers don’t really understand how it is the guides know who they are even though they do not give their names.  Can you explain how this happens?

The entities who answer these questions are part of the great spirit, the oneness of being, that energy force which all beings can tap into if they wish and are part of whether they wish it or not.  And because you are contained in bodies you feel separated and may feel confused by this communion, but know that all beings are of one energy force.  The beings that have spoken were using the physical world to commune with, you could think of it as our form of email. We are simply part of that oneness that all of you are part of.  And just by those asking the question we can and truly know who they are and where they are present in this great energy that surrounds all of you.

So you can tune into them and know exactly who they are and knowing also even beyond the questions what they are really asking or what they really need to know?

Yes

I understand that from my experiences talking to the guides,  but I think other people have difficulty in believing that.

It is not for you to present truth.  It is for you to seek your own truth. It is for them to seek theirs and in their process they shall find it.  There are many ways to the one, to understanding the oneness of all.  But each being doubts or believes as they choose fit for it will affect their very growth.  All beings are loved whether they believe in love or not, my dear.