using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		var text = "xy_yx_blaa_184\r\n\r\nis the act of composing and sending electronic messages, typically\r\nconsisting of alphabetic and numeric characters, between two or more\r\nusers of mobile phones, tablets, desktops/laptops, or other devices.\r\nText messages may be sent over a cellular network, or may also be sent\r\nvia an Internet connection.\r\n\r\nDerived\r\n\r\nQM\r\n\r\nSW\r\n\r\nxy_yx_blaa_199\r\n\r\nis the act of composing and sending electronic messages, typically\r\nconsisting of alphabetic and numeric characters, between two or more\r\nusers of mobile phones, tablets, desktops/laptops, or other devices.\r\nText messages may be sent over a cellular network, or may also be sent\r\nvia an Internet connection.\r\n\r\nDerived\r\n\r\nA\r\n\r\nSW";
		var pattern = @"^xy_yx_blaa_(\d+)(.*?)(^[A-D]\r?$|QM)+.*?(?:SW|Analyzing)";
		var results = Regex.Matches(text, pattern, RegexOptions.Multiline | RegexOptions.Singleline)
		    .Cast<Match>()
		    .Select(m => m.Value)
		    .ToList();
    	foreach (var r in results)
    		Console.WriteLine("{0}\n----------------", r);
	}
}

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