Is there is a way to save all the conversations that are happening in real time on the Openfire server?
I believe the Monitoring Service plugin is what you are after (which also offers chat archiving):
Afterr I install the plugin on the openfire clients… do you know how can I pull the conversations? or how do I monitoring them?
After installing the plugin, an Archiving tab should now be visible in the Openfire admin interface. Click on this, and under Archiving Settings on the left hand side, enable message archiving. From there the rest should be pretty easy to figure out.