using System;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		var line = "xxx abcdef abcdef xxx zxcvbn zxcvbn xxx poiuy poiuy";
        var splts = Regex.Split(line, @"xxx").Where(p => !string.IsNullOrWhiteSpace(p)).ToList();
        // Console.WriteLine(splts.Count());
        foreach (string match in splts)
		{
		    Console.WriteLine("'{0}'" , match);
		}
	}
}

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