Открываем файл catalog\model\catalog\product.php
Ищем:
if (!empty($data['filter_name'])) {
$implode = array();
$words = explode(' ', trim(preg_replace('/\s\s+/', ' ', $data['filter_name'])));
foreach ($words as $word) {
$implode[] = "pd.name LIKE '%" . $this->db->escape($word) . "%'";
}
if ($implode) {
$sql .= " " . implode(" AND ", $implode) . "";
}
if (!empty($data['filter_description'])) {
$sql .= " OR pd.description LIKE '%" . $this->db->escape($data['filter_name']) . "%'";
}
}
Заменяем:
if (!empty($data['filter_name'])) {
$implode = array();
$words = explode(' ', trim(preg_replace('/\s\s+/', ' ', $data['filter_name'])));
foreach ($words as $word) {
$implode[] = "pd.name LIKE '%" . $this->db->escape($word) . "%'";
$implodeh1[] = "pd.seo_h1 LIKE '%" . $this->db->escape($word) . "%'";
}
if ($implode) {
$sql .= " " . implode(" AND ", $implode) . "";
$sql .= " OR " . implode(" OR ", $implodeh1) . "";
}
if (!empty($data['filter_description'])) {
$sql .= " OR pd.description LIKE '%" . $this->db->escape($data['filter_name']) . "%'";
}
}
Как-то так...