How to Integrate Google Custom Search API in Website using PHP/MySQL?

Question

I have page subject.php, in which the records are fetching from mysql database in php and i want to add the google custom search api there. I add the google custom search api code before the table but when i search for some keywords, it say "No Result". I think, the code is not in right place, please help me to add the code in right place, which search for keywords in database.

Subject.php

<div class="col-md-6">

   <table class="table table-bordered">
    <tbody>

<script>
  (function() {
    var cx = '008166669750552411704:aldcxfluvae';
    var gcse = document.createElement('script');
    gcse.type = 'text/javascript';
    gcse.async = true;
    gcse.src = 'https://cse.google.com/cse.js?cx=' + cx;
    var s = document.getElementsByTagName('script')[0];
    s.parentNode.insertBefore(gcse, s);
  })();
</script>
<gcse:search>

    <?php

if(isset($_GET['category_name'])){

$category_name= $_GET['category_name'];

$get_detail= "select * from academic_work where category='$category_name' and status = 'Active'";

$run_detail= mysqli_query($con, $get_detail);

while($row_detail= mysqli_fetch_array($run_detail)){

$id= $row_detail['id'];
$student_email=$row_detail['student_email'];
$category=$row_detail['category'];
$title=$row_detail['title'];
$description=$row_detail['description'];
$pages=$row_detail['pages'];
$grade=$row_detail['grade'];
$name_processor=$row_detail['name_processor'];
$price=$row_detail['price'];
$discount_percent=$row_detail['discount_percent'];
$payment_commission=$row_detail['payment_commission'];
$pro_file=$row_detail['pro_file'];
$status=$row_detail['status'];
$date=$row_detail['date'];

echo "
      <tr>
        <td>
  <h6 style='color:green;'>$title</h6>
      <p style='color:black;'>
Description :- $description<br>
Name of Processor :- $name_processor<br>
Pages :- $pages<br>
Price :- $price<br></p>
 </td>
 </tr>
";
}
}

else {

$all_detail= "select * from academic_work where status = 'Active'";

$run_all_detail= mysqli_query($con, $all_detail);

while($row_all_detail= mysqli_fetch_array($run_all_detail)){

$id_all= $row_all_detail['id'];
$student_email_all=$row_all_detail['student_email'];
$category_all=$row_all_detail['category'];
$title_all=$row_all_detail['title'];
$description_all=$row_all_detail['description'];
$pages_all=$row_all_detail['pages'];
$grade_all=$row_all_detail['grade'];
$name_processor_all=$row_all_detail['name_processor'];
$price_all=$row_all_detail['price'];
$discount_percent_all=$row_all_detail['discount_percent'];
$payment_commission_all=$row_all_detail['payment_commission'];
$pro_file_all=$row_all_detail['pro_file'];
$status_all=$row_all_detail['status'];
$date_all=$row_all_detail['date'];

echo "
      <tr>
        <td>
  <h6 style='color:green;'>$title_all</h6>
      <p style='color:black;'>
Description :- $description_all<br>
Name of Processor :- $name_processor_all<br>
Pages :- $pages_all<br>
Price :- $price_all<br></p>
 </td>
 </tr>
";
}

}
?>
 </gcse:search>
 </tbody>
         </table>
  </div>