While there isn't a single official "story" by this exact name, the terms can be broken down as follows: fthtd087engsub : This likely refers to Episode 87 of a series with English subtitles ("engsub"). convert040729 : This often indicates a (April 7, 2029) or a specific conversion process used for the file format (like changing a video to MP4).
If you clarify what you're actually trying to do (convert a file? rename? search for something?), I can give you the exact steps or command. fthtd087engsub convert040729 min top