SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '' 
    OR cscart_product_descriptions.short_description IS NULL, 
    cscart_product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    94527, 94528, 94529, 94530, 94531, 94532, 
    94533, 94534, 94535, 94536, 94537, 
    94538, 94539, 94540, 94541, 94542, 
    94543, 94544, 94545, 94546, 94547, 
    94548, 94549, 94550, 94551, 94552, 
    94553, 94554, 94555, 94556, 94557, 
    94558, 94559, 94560, 94561, 94562, 
    94563, 94564, 94565, 94566, 94567, 
    94568, 94569, 94570, 94571, 94572, 
    94573, 94575
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00096

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "21.63"
    },
    "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": 48,
      "rows_produced_per_join": 48,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "16.83",
        "eval_cost": "4.80",
        "prefix_cost": "21.63",
        "data_read_per_join": "183K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (94527,94528,94529,94530,94531,94532,94533,94534,94535,94536,94537,94538,94539,94540,94541,94542,94543,94544,94545,94546,94547,94548,94549,94550,94551,94552,94553,94554,94555,94556,94557,94558,94559,94560,94561,94562,94563,94564,94565,94566,94567,94568,94569,94570,94571,94572,94573,94575)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
94527
94528
94529
94530
94531
94532
94533
94534
94535
94536
94537
94538
94539
94540
94541
94542
94543
94544
94545
94546
94547
94548
94549
94550
94551
94552
94553
94554
94555
94556
94557
94558
94559
94560
94561
94562
94563
94564
94565
94566
94567
94568
94569
94570
94571
94572
94573
94575