How to choose the right torrent

Hello,

I’m a newbie with seed boxes. I have an account at useed.fr with everything installed. I wanted to seed my torrents when finished to have a good ratio on yggtorrent but no uploading connections. I chose a torrent with over 1200 leechers but no upload. And it’s the same with every torrent I chose…

Any advices about where might be the problem ? The torrent client is ruTorrent