SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    12554, 12555, 12556, 12557, 12558, 12559, 
    12560, 12561, 12562, 12563, 12564, 
    12565, 12566, 12567, 12568, 12569, 
    12570, 12571, 12572, 12573, 12574, 
    12575, 12576, 12577, 12578, 12579, 
    12580, 12581, 12582, 12583, 12584, 
    12585, 12586, 12587, 12588, 12589, 
    12590, 12591, 12592, 12593
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00079

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "40.41"
    },
    "table": {
      "table_name": "cscart_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": 40,
      "rows_produced_per_join": 40,
      "filtered": "100.00",
      "index_condition": "((`test2_gaseus`.`cscart_product_descriptions`.`product_id` in (12554,12555,12556,12557,12558,12559,12560,12561,12562,12563,12564,12565,12566,12567,12568,12569,12570,12571,12572,12573,12574,12575,12576,12577,12578,12579,12580,12581,12582,12583,12584,12585,12586,12587,12588,12589,12590,12591,12592,12593)) and (`test2_gaseus`.`cscart_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "36.41",
        "eval_cost": "4.00",
        "prefix_cost": "40.41",
        "data_read_per_join": "182K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "meta_keywords",
        "meta_description",
        "search_words",
        "promo_text",
        "unit_name"
      ]
    }
  }
}