using System;
using System.Linq;
using System.Collections.Generic;
using System.Text.RegularExpressions;
public class Test
{
	public static void Main()
	{
		 var strs = new List<string> {"this is a test for <<bob>> who like <<books>>",
									  "test 2 <<frank>> likes nothing",
                                  "test 3 <<what>> <<on>> <<earth>> <<this>> <<is>> <<too>> <<much>>." };
		 foreach (var s in strs) 
		 {
		 	var results = Regex.Matches(s, @"<<(.*?)>>", RegexOptions.Singleline)
		 		.Cast<Match>()
		 		.Select(x => x.Groups[1].Value);
			Console.WriteLine(string.Join(", ", results));
		 }
 
	}
}

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