How do I ask for an informational chat? - 7 months and counting

I sent 5 messages on a professional network and got two replies. Some people reply with short answers.

I wrote three short lines: who I am, why them and a small ask for fifteen minutes. About one in four said yes.

Thanks for writing this out. I went through something close to it 7 months ago, and it got easier once I kept a simple log of every call and form.