how to override the HTML of the search results page?
Hope this will help you,

In Drupal 7, you can also achieve this

Using theme_search_results OR theme_search_result to override search results page.


theme_search_results : invoked for the search result page.

OR 
theme_search_result : invoked to render a single result

Both these theme functions used in a template file (search-results.tpl.php and search-result.tpl.php).

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