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 (
    88058, 84851, 88037, 88059, 88060, 87907, 
    87940, 88091, 88090, 88087, 88086, 
    93150, 93151, 93152, 93153, 93154, 
    93155, 93156, 93157, 93158, 93159, 
    93789, 93795, 93796, 93797, 94448, 
    94450, 94451, 94504, 94796, 94797, 
    94798, 94799, 94800, 94801, 94802, 
    94803, 94804, 94805, 94806, 94807, 
    94808, 94809, 94810, 94823, 94824, 
    94825, 94826
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00103

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 (88058,84851,88037,88059,88060,87907,87940,88091,88090,88087,88086,93150,93151,93152,93153,93154,93155,93156,93157,93158,93159,93789,93795,93796,93797,94448,94450,94451,94504,94796,94797,94798,94799,94800,94801,94802,94803,94804,94805,94806,94807,94808,94809,94810,94823,94824,94825,94826)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
84851 nuie Lawton 550mm Basin & Pedestal
87907 nuie Round Vessel 358 x 368 x 137mm
87940 Old London Chancery 500mm Basin 1 Tap Hole
88037 Old London Richmond 515mm Cloakroom Basin
88058 Old London Richmond 560mm 3 Tap Hole Basin
88059 Old London Richmond 500mm Basin 2 Tap Hole
88060 Old London Richmond 500mm Basin 1 Tap Hole
88086 nuie Melbourne 350mm Wall Hung Basin
88087 nuie Melbourne 450mm Wall Hung Basin
88090 nuie Melbourne 350mm Wall Hung Basin
88091 nuie Melbourne 450mm Wall Hung Basin
93150
93151
93152
93153
93154
93155
93156
93157
93158
93159
93789
93795
93796
93797
94448
94450
94451
94504
94796
94797
94798
94799
94800
94801
94802
94803
94804
94805
94806
94807
94808
94809
94810
94823
94824
94825
94826