If you are looking for German (or German + English dual language) content it can be very hard to find stuff on public torrent trackers and it's pretty hard to get onto private German trackers - but don't worry, there is a solution:
Usenet and the indexer sceneNZBs.com that specialises in German releases have got you covered!
If you want to automate the search for German Dual Language content using Radarr/Sonarr I made a guide (that also works for torrents too): https://github.com/PCJones/radarr-sonarr-german-dual-language
May I ask what I should look for in the log files to detect this (and so I can configure fail2ban correctly)?