SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    64625, 64624, 64616, 64617, 64615, 64614, 
    64622, 64623, 64626, 64621, 64620, 
    65851
  )

Query time 0.00050

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 (64625,64624,64616,64617,64615,64614,64622,64623,64626,64621,64620,65851)"
    }
  }
}

Result