Hi Thierry,
For viewing the Topic which you have created for marketing leads can be seen from following steps.
1. you need to use the HTML client for the same.
2. when creating a topic , Enter into adaption mode and click on change master lay-out. you will see change for all users on the top and then add your query for the relevant topic and then end adoption mode.
3. Go into your deal finder dash-board report and see the topic created.
Regards,
Devendra