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 (
    95938, 95939, 95942, 95943, 96213, 96214, 
    96215, 96216, 96217, 96218, 96219, 
    96220, 96221, 96222, 96223, 96224, 
    96225, 96226, 96227, 96228, 96229, 
    96230, 96231, 96232, 96233, 96234, 
    96235, 96236, 96237, 96238, 96239, 
    96240, 96241, 96242, 96243, 96244, 
    96334, 96336, 96338, 96340, 96341, 
    96342, 96343, 96344, 96345, 96346, 
    96347, 96348
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00088

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 (95938,95939,95942,95943,96213,96214,96215,96216,96217,96218,96219,96220,96221,96222,96223,96224,96225,96226,96227,96228,96229,96230,96231,96232,96233,96234,96235,96236,96237,96238,96239,96240,96241,96242,96243,96244,96334,96336,96338,96340,96341,96342,96343,96344,96345,96346,96347,96348)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
95938
95939
95942
95943
96213
96214
96215
96216
96217
96218
96219
96220
96221
96222
96223
96224
96225
96226
96227
96228
96229
96230
96231
96232
96233
96234
96235
96236
96237
96238
96239
96240
96241
96242
96243
96244
96334
96336
96338
96340
96341
96342
96343
96344
96345
96346
96347
96348