How to find people who are solo poly and not in primary relationships?

Edited to add: thanks to everyone who took the time to answer my post with clarifications, explanations, definitions, book recommendations, personal anecdotes and advice. I really appreciate it.

Original Post

Hi there, I'm feeling frustrated with the poly community because it mostly consists of people who have primary partners and want to play with others. This is great for people in relationships. But what about singles? I want to date others who are single, for that relationship to deepen potentially, but for us both to be comfortable with more than one partner. I want to consider myself with several partners and for them to have several if they want

But how do you avoid dating those in primary relationships?

They are the only poly types I meet.

Once you're relationship deepens, how to avoid the 'primary relationship' trap?

I believe some people are just always in couples and some are mostly single. Noone talks about the 36% who are single most of the time