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 (
    82485, 89533, 85606, 85605, 89532, 93902, 
    93903, 93904, 93905, 93906, 93910, 
    93911, 93912, 94965, 94966, 94967, 
    94968, 94969, 94970, 94971, 94972, 
    94973, 94974, 94975, 94976, 94977, 
    94978, 94979, 94980, 94981, 94982, 
    95450, 95459, 95463, 95511, 95512, 
    95513, 95517, 95518, 95519, 95527, 
    95528, 95542, 95543, 95544, 96792, 
    96848, 96849, 96850, 96851, 96852, 
    96853, 96854, 96855, 96856, 96857, 
    96858, 96859, 96860, 96861, 96862, 
    96863, 96864, 96865, 98509, 98510, 
    100187, 100188, 100189, 100190, 100191, 
    100195, 100196, 100197, 100298, 100300
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00215

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "34.23"
    },
    "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": 76,
      "rows_produced_per_join": 76,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "26.64",
        "eval_cost": "7.60",
        "prefix_cost": "34.24",
        "data_read_per_join": "289K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (82485,89533,85606,85605,89532,93902,93903,93904,93905,93906,93910,93911,93912,94965,94966,94967,94968,94969,94970,94971,94972,94973,94974,94975,94976,94977,94978,94979,94980,94981,94982,95450,95459,95463,95511,95512,95513,95517,95518,95519,95527,95528,95542,95543,95544,96792,96848,96849,96850,96851,96852,96853,96854,96855,96856,96857,96858,96859,96860,96861,96862,96863,96864,96865,98509,98510,100187,100188,100189,100190,100191,100195,100196,100197,100298,100300)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
82485 nuie Pacific 800mm Bi-Fold Door - 4mm Glass - Polished Chrome
85605 nuie Ella 760mm Bi-Fold Door - 5mm Glass - Satin Chrome
85606 nuie Ella 800mm Bi-Fold Door - 5mm Glass - Satin Chrome
89532 nuie Enclosures Rene 800mm Bi-Fold Shower Door - Satin Chrome
89533 nuie Enclosures Rene 900mm Bi-Fold Shower Door - Satin Chrome
93902
93903
93904
93905
93906
93910
93911
93912
94965
94966
94967
94968
94969
94970
94971
94972
94973
94974
94975
94976
94977
94978
94979
94980
94981
94982
95450
95459
95463
95511
95512
95513
95517
95518
95519
95527
95528
95542
95543
95544
96792
96848
96849
96850
96851
96852
96853
96854
96855
96856
96857
96858
96859
96860
96861
96862
96863
96864
96865
98509
98510
100187
100188
100189
100190
100191
100195
100196
100197
100298
100300