Depending on where the data is coming from (and if you happen to be dealing with utf-8 encoded text), it's possible that you may be dealing with a "hyphen-like" character that is not the traditional ASCII hyphen (\x2d) - it could be any of [\x{2010}\x{2011}\x{2013}\x{2014}] ("hyphen", "non-breaking hyphen", "em dash", "en dash").

In that case, provided that you are correctly ingesting the text data as utf8, using the regex "dot" wildcard (and ignoring case distinctions) is The Right Thing:  /x.ray/i