A useful place to search for patents, worldwide (includes US, Europe): http://worldwide.espacenet.com/
European trade mark search: https://www.tmdn.org/tmview/welcome
European registered design search: https://www.tmdn.org/tmdsview-web/welcome
USPTO trade mark search: Search trademark database | USPTO
NB just because you can’t find something with these doesn’t mean it doesn’t exist, there or anywhere else.