1. <form action="" id="searchForm">
       <input type="text" placeholder="Search..." name="s" id="food">
       <input type="submit" value="Search">
   </form>
   <!-- the result of the search will be rendered inside this div -->
   <div id="result">
   </div>

my script jquery :

<script>
    $('#searchForm').submit(function(event) {

        // Stop la propagation par défaut
        event.preventDefault();

        // Récupération des valeurs
        var $form = $(this),
            term = $form.find( "input[name='s']" ).val(),
            url = $form.attr( "action" );

        // Envoie des données
        var posting = $.post( 'more.php', { s: term } );

        // Reception des données et affichage
        posting.done(function(data) {
            var content = $(data).find('#content');
            console.log('valeur ' + term);
            $('#result').empty().append(content);
        });

    });

</script>

And my php file :

I don't understand why it doesn't work can you help me please ?

<?php

$bdd = new PDO('mysql:host=localhost;dbname=chappy', 'root', 'root');
$data = $bdd->query('SELECT * FROM Valnut WHERE Aliment LIKE "%'.$_POST['food'].'%"');

?>
    <ul>
        <?php while ($a = $data->fetch()){
            ?>
            <li><?= $a['Aliment']. ' | '.$a['Kcal']. ' Kcal'   ;?></li>
            <?php
        }
        ?>
    </ul>