SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    18034, 8292, 10844, 10667, 8181, 11109, 
    8163, 18037, 8174, 12394, 13546, 7651, 
    8083, 8186, 11107, 11108
  )

Query time 0.00070

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_products",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "rows": 16,
          "filtered": 100,
          "index_condition": "cscart_products.product_id in (18034,8292,10844,10667,8181,11109,8163,18037,8174,12394,13546,7651,8083,8186,11107,11108)"
        }
      }
    ]
  }
}