<?php
$output = '';
if(isset($_GET['q']) && $_GET['q'] !== ' ') {
    $searchq = $_GET['q'];

    $q = mysqli_query($db, "SELECT * FROM article WHERE title LIKE '%$searchq%' OR content LIKE '%$searchq%'") or die(mysqli_error());
    $c = mysqli_num_rows($q);
    if($c == 0) {
        $output = 'No search results for <strong>"' .   $searchq    .   '"</strong>';
    } else {
        while($row = mysqli_fetch_array($q)) {
            $id = $row['id'];
            $title = $row ['title'];
            $content = $row ['content'];
        $output .= '<a href="article.php?id=' .$id. '">

            <h3>'.$title.'</h3></a>'.$content.'';
        }
    }
} else {
        header("location: ./");
}
print("$output");
mysqli_close($db);

<?php
if(!empty($_GET['id']))
{
   $sql = "
SELECT id, title, content
FROM article
";
    // then do the query, etc....
}

$results = $db->query($sql);

if($results->num_rows) {
    While($row = $results->fetch_object()) {
        $title = htmlentities($row->title);
        $content = nl2br(htmlentities($row->content));
        echo "

<h2>{$row->title}</h2>
{$row->content}


";
    }
} else {
    echo 'No Results';
}
?>