In order that the documents received in the territory of Ukraine have the legal force in Germany they shall be legalized according to the international norms.
You can see below the examples of apostille for Germany. Depending on the document you may be required the apostille in different ministries.
You can see on the page “Apostille on documents” the more detailed information about affixing the Apostille stamp on the documents issued in Ukraine, and see the examples of already legalized documents you can on the link «Examples of apostille stamps».
Schematically the apostillization procedure looks like this.