XML : How to use Sql type of queries against XML file

          XmlTextReader xmlreader = new XmlTextReader(Server.MapPath("MoviesData.xml"));          DataSet ds = new DataSet();          ds.ReadXml(xmlreader);          xmlreader.Close();          if (ds.Tables.Count != 0)          {              DataList1.Visible = true;              DataList1.DataSource = ds;              DataList1.DataBind();          }    

I want the specific information from the XML file like moviename, movie description, actors, genres. as well as i want to use the like operator wants to check based upon the user input into textbox how to check it i am not understanding can somebody help me.