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 (
    97712, 98054, 98055, 98056, 98057, 98058, 
    98059, 98060, 98061, 98062, 98063, 
    98064, 98065, 98066, 98067, 98068, 
    98069, 98070, 98071, 98072, 98073, 
    98074, 98075, 98076, 98077, 98078, 
    98079, 98080, 98081, 98082, 98083, 
    98523, 98524, 98525, 98526, 98527, 
    98528, 98529, 98530, 98531, 98532, 
    98533, 98534, 98535, 98536, 98537, 
    98557, 98558, 98559, 98773, 98774, 
    98775, 98776, 98777, 98778, 98779, 
    98780, 98781, 98782, 98783, 98784, 
    98785, 98786, 98787, 98788, 98789, 
    98790, 98791, 98792, 98793, 98794, 
    98795, 98796, 98797, 98798, 98799, 
    98800, 98801, 98802, 98803, 98804, 
    98805, 98806, 98807, 98808, 98809, 
    98810, 98811, 98812, 98813, 98814, 
    98874, 98875, 98876, 98877, 99056
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00243

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 (97712,98054,98055,98056,98057,98058,98059,98060,98061,98062,98063,98064,98065,98066,98067,98068,98069,98070,98071,98072,98073,98074,98075,98076,98077,98078,98079,98080,98081,98082,98083,98523,98524,98525,98526,98527,98528,98529,98530,98531,98532,98533,98534,98535,98536,98537,98557,98558,98559,98773,98774,98775,98776,98777,98778,98779,98780,98781,98782,98783,98784,98785,98786,98787,98788,98789,98790,98791,98792,98793,98794,98795,98796,98797,98798,98799,98800,98801,98802,98803,98804,98805,98806,98807,98808,98809,98810,98811,98812,98813,98814,98874,98875,98876,98877,99056)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
97712
98054
98055
98056
98057
98058
98059
98060
98061
98062
98063
98064
98065
98066
98067
98068
98069
98070
98071
98072
98073
98074
98075
98076
98077
98078
98079
98080
98081
98082
98083
98523
98524
98525
98526
98527
98528
98529
98530
98531
98532
98533
98534
98535
98536
98537
98557
98558
98559
98773
98774
98775
98776
98777
98778
98779
98780
98781
98782
98783
98784
98785
98786
98787
98788
98789
98790
98791
98792
98793
98794
98795
98796
98797
98798
98799
98800
98801
98802
98803
98804
98805
98806
98807
98808
98809
98810
98811
98812
98813
98814
98874
98875
98876
98877
99056