如何在wordpress搜索查询中删除/替换倾斜的双引号“with”？

I'm trying to replace slanted double quotes ″ with regular double quotes " in wordpress (woocomerce) search query because the first example returns no products.

Example search:

CUBE ACID SIC PURE 28″ RILink (no results)
CUBE ACID SIC PURE 28" RILink (correct result)

I tried to replace the ″ characted with this code using get_search_query filter:

add_filter('get_search_query', 'my_search_query');

function my_search_query( $s ) {
  $characters = '″'; // Replace this
  $replace_with = '"'; // with this

  if ( is_array($s) ) {
    if ( isset($s['s']) && !$s['_ajax_search'] ) 
      $s['s'] = str_replace(str_split($characters), $replace_with, $s['s']);      
  } else {
    $s = str_replace(str_split($characters), $replace_with, $s);
  }

  return $s; 
}

but that only changed the search results text to CUBE ACID SIC PURE 28""" RILink and the search query url stayed the same ?s=CUBE+ACID+SIC+PURE+28″+RILink&post_type=product with the incorrect double quote character.

What is the correct way to replace quotes in search query url so the search returns results as expected?