I want to make my html button work with php

I create a button using html, and using array_key_exists to call function function from php when button is pressed but it doesn't do anything executeBoundSQL is just a function from php

<form method="POST" action="docAppts.php">
<!--refresh page when submit-->

<p><input type="text" name="did" size="6">
<!--define two variables to pass the value-->
<input type="submit" value="search" name="searchh"></p>
</form>



if ($db_conn) {
$result=executePlainSQL(" select * from doctor");
printResult($result);
if (array_key_exists('searchh', $_POST)) {
    echo"show me";
    $tuple=array(
         ":bind1"=> $_POST['did']
    );
    $alltuples=array(
         $tuple
    );
    echo "<br> print table <br>";
//  executePlainSQL("Drop table :tablname");
    //echo':tablename';
    $result=executeBoundSQL("select * from doctor where  did=:bind1", $alltuples);

    printResult1($result);
    // Create new table...
    //echo "<br> creating new table <br>";
    //executePlainSQL("create table tab1 (nid number, name varchar2(30), primary key (nid))");
    OCICommit($db_conn);

} }