You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <searchinfo totalhits="2" />
    <search>
      <p ns="0" title="Advanced configuration" snippet="By default, this is &amp;#039;&amp;#039;true&amp;#039;&amp;#039;, &lt;span class=&#039;searchmatch&#039;&gt;meaning&lt;/span&gt; Wikipedia+ checks whether pages exist on the corresponding sites before pos&#10;" size="1721" wordcount="274" timestamp="2013-05-28T10:02:02Z" />
      <p ns="0" title="Developing Wikipedia Plus" snippet="...modern search engines. W3C&amp;#039;s semantic web language (RDF) associates each &amp;#039;&lt;span class=&#039;searchmatch&#039;&gt;meaning&lt;/span&gt;&amp;#039; with a separate URI (web address).&#10;" size="1913" wordcount="293" timestamp="2016-08-25T07:38:12Z" />
    </search>
  </query>
</api>