I've being thinking really hard about how break this down in a way to understand and as a last resort I'm turning to algebra

You have in your mind S, you want to talk about S but you’re not used to it. So you think talking about R will naturally lead to S.

You go over and say hey what do you think about R or Q?

Now they will, because you never even hinted at S. They will talk about their own experience of R or even P in an honest way.

You get dejected because you were hoping she would lead things to S and they didn’t.

If you were to go over and say "hey, I wanna talk about some S with you" Then you’re on the right path.