The beginning is text followed by garbage characters.It shows the same thing as if you had downloaded the torrent file and opened it in a text editor. The test pipe grabs what it can - the text at the front.
Unfortunately, this wont be possible today. The torrent file is not in a format that can be parsed by YQL. When you give the URL to the "html" table, you're actually asking it to treat the torrent as a HTML and since it isnt it cannot be parsed.
Aside: The formats supported today include XML(RSS, ATOM, HTML), JSON and CSV. If the torrent metadata can be transformed into any of these formats, then YQL will readily grok it. That said, please stay tuned for our upcoming releases where we do intend to address such custom cases by providing hooks.