Do you connect to Microsoft Dynamics 365 (online) instance with power bi desktop?
Do you query data via appending additional URL parts to Dynamics 365 Web API?
Do you expand the 'connection' field in the "contact" table to get related fields?
When you connect to CRM you will notice that there are values in some entities that are highlighted yellow. You can choose columns from these related objects. (This is also a setting in Options that you can disable. Under Current File -> Data Load -> Relationships - "Import relationships from data sources")
Here are references you may get useful idea from.