Adding/removing specific elements from xml file, in Qt?

I have a XML Document, like this:

<?xml version="1.0" encoding="UTF-8"?>
<items>
<item s_no="1">
    <title>title_1</title>
    <path>path1</path>
    <desc>descriptoion1</desc>
</item>

<item s_no="2">
    <title>title_2</title>
    <path>path2</path>
    <desc>descriptoion2</desc>
</item>

This is generated from QXmlStreamWriter in Qt. I want a function to add <item> tag with all elements like <title>, <path> etc. and I want a function to remove an item tag by identifying s_no attributes. All this should be done, without affecting any other content in the file.

I've searched a lot,I know there are similar questions, I've tried some code but it didn't worked. Are there any functions that do this, in QDomDocument?