Easier way is to use a Regex:
string s = "Tendulkar,Sachin(srt);Dhoni,MS(msd);Sehwag,Virender(viru);D'Souza,Tim(tdsc)";
Regex reg = new Regex(@"(?<=\().+?(?=\))");
MatchCollection matches = reg.Matches(s);
List<string> separated = new List<string>();
foreach (Match m in matches)
{
separated.Add(m.Value);
}