Stop Indexing

You Can Stop Indexing of author, date archive, category, tag material in search engines. and stop indexing duplicate content.

How To Do Manually-

>> open your wordpress’s header.php file.
>> paste these code in head section

<?php
// Do not index author, date archive, category, tag and search result
if( is_author() | is_date() | is_search() | is_category() | is_tag() ) {
_e('<meta name="robots" content="noindex,follow" />');
}
?>

>> Then SAVE your File.