SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    65703, 64905, 64871, 64868, 64863, 64861, 
    64872, 64898, 64947, 64864, 65548, 
    64857
  )

Query time 0.00082

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,
      "attached_condition": "cscart_products.product_id in (65703,64905,64871,64868,64863,64861,64872,64898,64947,64864,65548,64857)"
    }
  }
}

Result