SELECT 
  ushop_product_descriptions.product_id, 
  ushop_product_descriptions.unit_name 
FROM 
  ushop_product_descriptions 
WHERE 
  ushop_product_descriptions.product_id IN (
    430, 440, 432, 407, 409, 411, 402, 395, 
    404
  ) 
  AND ushop_product_descriptions.lang_code = 'es'

Query time 0.00067

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "6.31"
    },
    "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": 9,
      "rows_produced_per_join": 9,
      "filtered": "100.00",
      "index_condition": "((`marketplace`.`ushop_product_descriptions`.`product_id` in (430,440,432,407,409,411,402,395,404)) and (`marketplace`.`ushop_product_descriptions`.`lang_code` = 'es'))",
      "cost_info": {
        "read_cost": "5.41",
        "eval_cost": "0.90",
        "prefix_cost": "6.31",
        "data_read_per_join": "57K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "unit_name"
      ]
    }
  }
}