SELECT 
  ushop_product_descriptions.product_id, 
  ushop_product_descriptions.unit_name 
FROM 
  ushop_product_descriptions 
WHERE 
  ushop_product_descriptions.product_id IN (
    517, 525, 511, 489, 516, 483, 513, 496, 
    479, 519, 509, 510, 488, 512, 478, 490, 
    503, 482, 514, 492, 507, 521, 520, 502, 
    508, 480, 515, 506, 518, 497, 505, 500, 
    495
  ) 
  AND ushop_product_descriptions.lang_code = 'es'

Query time 0.00057

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "23.11"
    },
    "table": {
      "table_name": "ushop_product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 33,
      "rows_produced_per_join": 33,
      "filtered": "100.00",
      "index_condition": "((`marketplace`.`ushop_product_descriptions`.`product_id` in (517,525,511,489,516,483,513,496,479,519,509,510,488,512,478,490,503,482,514,492,507,521,520,502,508,480,515,506,518,497,505,500,495)) and (`marketplace`.`ushop_product_descriptions`.`lang_code` = 'es'))",
      "cost_info": {
        "read_cost": "19.81",
        "eval_cost": "3.30",
        "prefix_cost": "23.11",
        "data_read_per_join": "209K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "unit_name"
      ]
    }
  }
}