Call detail records generated by 3CX are in the PostgreSQL database, in the table "calldetails". You can explore it in your installation using a PostgreSQL client like this: http://sqlmanager.net/products/postgresql/manager/
In that table you have information related to the call, but there is no information about what the user did into the callflow. If you need that information, you will need to generate call records in the VAD callflow using a File Management component or a Database Access component, so you can store them where you need, and with the data and format you need.