public static void Main()
var html = @"http://eng.jtc.com.tw/product/?mode=data&id=691&top=2";
HtmlWeb web = new HtmlWeb();
var htmlDoc = web.Load(html);
var htmlBody = htmlDoc.DocumentNode.SelectSingleNode("//body");
var node = htmlBody.Element("p");
var whatUrLookingFor = htmlDoc.GetElementbyId("content_description").InnerHtml;
Console.WriteLine(whatUrLookingFor);