Cold messages to people in my field, do they work? - any advice?

I want to talk to people in a new field but I hate cold messages. I worry about bothering people. How do you phrase the request?

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.