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-continue>
    <pageswithprop gpwpcontinue="1774" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1302" ns="4" title="VLOS:Câu thường hỏi" contentmodel="wikitext" pagelanguage="vi" touched="2012-02-27T15:41:46Z" lastrevid="67529" counter="14473" length="6170" />
      <page pageid="1306" ns="10" title="Bản mẫu:Hình tượng" contentmodel="wikitext" pagelanguage="vi" touched="2017-02-04T10:33:14Z" lastrevid="91750" counter="2129" length="3210" />
      <page pageid="1307" ns="10" title="Bản mẫu:Liên kết chọn lọc" contentmodel="wikitext" pagelanguage="vi" touched="2012-02-27T14:22:51Z" lastrevid="1316" counter="1326" length="2747" new="" />
      <page pageid="1312" ns="10" title="Bản mẫu:Sao chọn lọc" contentmodel="wikitext" pagelanguage="vi" touched="2012-02-27T17:31:35Z" lastrevid="1321" counter="1355" length="1964" new="" />
      <page pageid="1383" ns="0" title="Các câu nói hay liên quan đến khoa học" contentmodel="wikitext" pagelanguage="vi" touched="2017-05-20T17:11:50Z" lastrevid="15189" counter="6598" length="2520" />
      <page pageid="1390" ns="10" title="Bản mẫu:Mục lục chữ cái" contentmodel="wikitext" pagelanguage="vi" touched="2012-02-27T22:17:18Z" lastrevid="1473" counter="341" length="345" new="" />
      <page pageid="1422" ns="4" title="VLOS:Người sáng lập" contentmodel="wikitext" pagelanguage="vi" touched="2012-02-27T15:45:15Z" lastrevid="69671" counter="13001" length="1836" />
      <page pageid="1467" ns="0" title="Tủ sách Khoa học" contentmodel="wikitext" pagelanguage="vi" touched="2018-01-20T03:46:54Z" lastrevid="142596" counter="225951" length="2565" />
      <page pageid="1677" ns="2" title="Thành viên:Đỗ Quốc Bảo" contentmodel="wikitext" pagelanguage="vi" touched="2012-04-07T12:49:48Z" lastrevid="3187" counter="10629" length="1456" />
      <page pageid="1723" ns="14" title="Thể loại:Đề thi Toán học" contentmodel="wikitext" pagelanguage="vi" touched="2012-04-14T16:21:38Z" lastrevid="4333" counter="5597" length="303" />
    </pages>
  </query>
</api>