SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    4669, 4670, 6906, 4674, 4671, 4672, 4673
  )

Query time 0.00028

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": 7,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (4669,4670,6906,4674,4671,4672,4673)"
    }
  }
}