SELECT *
FROM eshop_products
LEFT JOIN eshop_products_features ON eshop_products.id = eshop_products_features.product_id
JOIN eshop_features ON eshop_products_features.feature_id=eshop_features.id
WHERE (eshop_features.id='1' OR eshop_features.id=2) and (eshop_products_features.value="MacOS X" or eshop_products_features.value="Ноутбук") GROUP BY eshop_products.id
SELECT *
FROM eshop_products
LEFT JOIN eshop_products_features ON eshop_products.id = eshop_products_features.product_id
WHERE eshop_products_features.value = 'MacOS X' OR
eshop_products_features.value = 'Ноутбук'