To make sure others can see you on the Community stream, please go to your Profile (small icon of your profile photo in the top right of your screen) and you will see a toggle 'Show me in the Community' that you can enable if you want to be visible to others.
If you made sure that your profile is visible, but you still don't get enough messages from new chat partners, how about you add a new Topic to your profile? This really might help others start a conversation with you.