Well, only some things are added to your household insurance. Some losses are not covered by your home content insurance in Germany. These include;
Furniture in your home that is not yours. Your liability insurance will cover the loss of belongings that do not belong to you.
Your household insurance does not cover loss due to your pet. Separate pet insurance will cover such losses.
If you have an aircraft, boat, or bike, you will not get them covered with your household insurance. It would be best to get motorised vehicle insurance to cover such losses.