using System;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		string input = "((isoCode=s)||(isoCode=a))&&(title=s)&&((ti=2)&&(t=2))||(t=2&&e>5)";
	    string pattern = @"\(((?>\((?<DEPTH>)|\)(?<-DEPTH>)|.?)*(?(DEPTH)(?!)))\)|&{2}|\|{2}";
	    MatchCollection matches = Regex.Matches(input, pattern);
	    foreach (Match match in matches)
	    {
	        Console.WriteLine(match.Groups[1].Success ? match.Groups[1].Value : match.Groups[0].Value);
	    }
	}
}

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