Make sure your qBittorrent client is up to date, as this will ensure compatibility with the latest search plugin updates.
(If you want, I can search GitHub and return a shortlist of current repositories and their last-updated dates.) 1337x qbittorrent search plugin
This is an unofficial plugin, not affiliated with 1337x. Use it only for content you have the legal right to download. Make sure your qBittorrent client is up to