Regex PhoneNumberRegex = new Regex(@"((?:\+\d{0,2})?(?:\(?\d{3}\)?[\s-]?)?(?:\d{2,3}[\s-])(?:\d{2,3}[\s-])(?:\d{2,3}))");
var value = "Бла бла бла бла 055-555-55-55, 055-555-55-55, 555-55-55 ";
var phoneNumbers = (from Match match in PhoneNumberRegex.Matches(value) select match.Value).ToList();