In your "html code" just copy below script:
<!-- Starting of script-->
<script src='demo-to-prevent-copy-paste-on-blogger_files/googleapis.js'>
</script>
<script type='text/javascript'>
if (typeof document.onselectstart!="undefined" )
{
document.onselectstart=new Function ("return false" );
} else
{
document.onmousedown=new Function ("return false" ); document.onmouseup=new Function ("return true" );
}
</script>
<!-- Ending of script-->
<!-- Starting of script-->
<script src='demo-to-prevent-copy-paste-on-blogger_files/googleapis.js'>
</script>
<script type='text/javascript'>
if (typeof document.onselectstart!="undefined" )
{
document.onselectstart=new Function ("return false" );
} else
{
document.onmousedown=new Function ("return false" ); document.onmouseup=new Function ("return true" );
}
</script>
<!-- Ending of script-->