$sql = SELECT `brand`, COUNT(*) AS `count`
FROM products WHERE count > ? AND (`category`="igrushki") AND (`brand`="toy" OR `brand`="joy") AND (`age`="1-3year" OR `age`="12month" OR `age`="5 years") AND (price >= 55 BETWEEN price <= 1200) GROUP BY `brand`
$req = $mysqli->prepare($sql);
$req->bind_param('s', '1');
$req->execute();