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 (
    98742, 98743, 98744, 98745, 98746, 98747, 
    98748, 98749, 99570, 99571, 99572, 
    99573, 99580, 99581, 99582, 99583, 
    99584, 99585, 99586, 99587, 100067, 
    100068, 100069, 100070, 100071, 100072, 
    100150, 100151, 100152, 100153, 100154, 
    100155, 100156, 100169, 100170, 100171, 
    100172, 100173, 100174, 100175, 100176, 
    100177, 100178, 100179, 100180, 100321, 
    100322, 100323, 100324, 100325, 100326, 
    100602, 100603, 100604, 100605, 100606, 
    100607, 100608, 100609, 100610, 100611, 
    100654, 100655, 100656, 100657, 100658, 
    100696, 100697, 100698, 100699, 100884, 
    100885, 100886, 100887, 100900, 100901, 
    100902, 100903, 100904, 100907, 100908, 
    100909, 100910, 100913, 100914, 100915, 
    100916, 100917, 100918, 100919, 100920, 
    100921, 100922, 101112, 101113, 101114
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00133

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "43.24"
    },
    "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": 96,
      "rows_produced_per_join": 96,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "33.64",
        "eval_cost": "9.60",
        "prefix_cost": "43.24",
        "data_read_per_join": "366K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (98742,98743,98744,98745,98746,98747,98748,98749,99570,99571,99572,99573,99580,99581,99582,99583,99584,99585,99586,99587,100067,100068,100069,100070,100071,100072,100150,100151,100152,100153,100154,100155,100156,100169,100170,100171,100172,100173,100174,100175,100176,100177,100178,100179,100180,100321,100322,100323,100324,100325,100326,100602,100603,100604,100605,100606,100607,100608,100609,100610,100611,100654,100655,100656,100657,100658,100696,100697,100698,100699,100884,100885,100886,100887,100900,100901,100902,100903,100904,100907,100908,100909,100910,100913,100914,100915,100916,100917,100918,100919,100920,100921,100922,101112,101113,101114)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
98742
98743
98744
98745
98746
98747
98748
98749
99570
99571
99572
99573
99580
99581
99582
99583
99584
99585
99586
99587
100067
100068
100069
100070
100071
100072
100150
100151
100152
100153
100154
100155
100156
100169
100170
100171
100172
100173
100174
100175
100176
100177
100178
100179
100180
100321
100322
100323
100324
100325
100326
100602
100603
100604
100605
100606
100607
100608
100609
100610
100611
100654
100655
100656
100657
100658
100696
100697
100698
100699
100884
100885
100886
100887
100900
100901
100902
100903
100904
100907
100908
100909
100910
100913
100914
100915
100916
100917
100918
100919
100920
100921
100922
101112
101113
101114