SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    4754, 4745, 4938, 4760, 4747, 4746, 4748, 
    4903, 4750, 4749, 4753, 4752
  )

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_products",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 12,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (4754,4745,4938,4760,4747,4746,4748,4903,4750,4749,4753,4752)"
    }
  }
}