SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    1705, 1704, 1609, 1935, 1936, 1929, 1528, 
    1527, 1526, 1508, 1534, 1533
  )

Query time 0.00090

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 (1705,1704,1609,1935,1936,1929,1528,1527,1526,1508,1534,1533)"
    }
  }
}