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 (
    96162, 96163, 96164, 96165, 96166, 96167, 
    96168, 96169, 96170, 96171, 96172, 
    96173, 96174, 96175, 96189, 96195, 
    96196, 96197, 96198, 96199, 96200, 
    96201, 96209, 96212, 96349, 96537, 
    96559, 96560, 96561, 96842, 96843, 
    96844, 96845, 96846, 96847, 97057, 
    97058, 97059, 97060, 97061, 97062, 
    97063, 97064, 97065, 97066, 97067, 
    97068, 97069
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00110

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 (96162,96163,96164,96165,96166,96167,96168,96169,96170,96171,96172,96173,96174,96175,96189,96195,96196,96197,96198,96199,96200,96201,96209,96212,96349,96537,96559,96560,96561,96842,96843,96844,96845,96846,96847,97057,97058,97059,97060,97061,97062,97063,97064,97065,97066,97067,97068,97069)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
96162
96163
96164
96165
96166
96167
96168
96169
96170
96171
96172
96173
96174
96175
96189
96195
96196
96197
96198
96199
96200
96201
96209
96212
96349
96537
96559
96560
96561
96842
96843
96844
96845
96846
96847
97057
97058
97059
97060
97061
97062
97063
97064
97065
97066
97067
97068
97069