Patent Search Tools:

1. Espacenet of EPO:
https://worldwide.espacenet.com/?locale=en_EP

2. Global Dossier of USPTO:
https://globaldossier.uspto.gov/#/

3. Depatisnet of German patent office:
https://depatisnet.dpma.de/DepatisNet/depatisnet?action=basis

4. European Patent Register, the place to find procedural and legal status data:
https://register.epo.org/regviewer?lng=en