At the first look, i see 3 errors:
1.
string urlAddressofW = "https://google.com/search?q=" + ADDING;
2.
ADDING = PureTexttitle.Replace(" ", "+");
3.
if (responseW.StatusCode == HttpStatusCode.OK)
{
Stream receiveStreamW = responseW.GetResponseStream();
StreamReader readStreamW = null;
if (responseW.CharacterSet == null)
{
readStreamW = new StreamReader(receiveStreamW);
}
else
{
readStreamW = new StreamReader(receiveStreamW,
Encoding.GetEncoding(responseW.CharacterSet));
readStreamW.ToString();
}
Note: Google returns such of document:
<!doctype html><html lang="pl"><head><meta charset="UTF-8"><meta content="/images/branding/googleg/1x/googleg_standard_color_128dp.png" itemprop="image"><title>General election 2019: Greens call for £100bn a year for climate action -
<!--
<script nonce="FdWZZ+ZWymCQ/pKGYdroJA==">(function(){var e='YfDgXcOLDZ-70PEPlJ2wmA4';(function(){var a=e,b=window.performance&&window.performance.navigation;b&&2==b.type&&window.ping("/gen_204?ct=backbutton&ei="+a);}).call(this);})();(function(){var b=[function(){google.tick&&google.tick("load","dcl")}];google.dclc=function(a){b.length?b.push(a):a()};function c(){for(var a;a=b.shift();)a()}window.addEventListener?(document.addEventListener("DOMContentLoaded",c,!1),window.addEventListener("load",c,!1)):window.attachEvent&&window.attachEvent("onload",c);}).call(this);(function(){(function(){google.csct={};google.csct.ps='AOvVaw3FMWI9xeFwYcVhHj3sXm62\x26ust\x3d1575109089244484';})();})();(function(){(function(){google.csct.rd=true;})();})();google.drty&&google.drty();</script></body></html>
Note #2: I'd avoid of creating new objects of:
HttpWebRequest
and
HttpWebResponse
unless it is necessary to go through the results of first request.