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 (
    88904, 90824, 90825, 87232, 87233, 87237, 
    87238, 87242, 87243, 87247, 87248, 
    84251, 84256, 87580, 87595, 87610, 
    88791, 84250, 84255, 87578, 87579, 
    87593, 87594, 87608, 87609, 88151, 
    88153, 88789, 88790, 87653, 87667, 
    87674, 87681, 87702, 87710, 87711, 
    87724, 87725, 87652, 87658, 87666, 
    87672, 87673, 87679, 87680, 87686, 
    87701, 87707
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00087

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 (88904,90824,90825,87232,87233,87237,87238,87242,87243,87247,87248,84251,84256,87580,87595,87610,88791,84250,84255,87578,87579,87593,87594,87608,87609,88151,88153,88789,88790,87653,87667,87674,87681,87702,87710,87711,87724,87725,87652,87658,87666,87672,87673,87679,87680,87686,87701,87707)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
84250 Hudson Reed 1700mm Straight Bath Front Panel & Plinth - Satin Anthracite
84251 Hudson Reed 1800mm Straight Bath Front Panel & Plinth - Satin Anthracite
84255 Hudson Reed 1700mm Straight Bath Front Panel & Plinth - Satin Green
84256 Hudson Reed 1800mm Straight Bath Front Panel & Plinth - Satin Green
87232 Old London Straight Bath Front Panel 1700mm - Storm Grey
87233 Old London Straight Bath Front Panel 1800mm - Storm Grey
87237 Old London Straight Bath Front Panel 1700mm - Twilight Blue
87238 Old London Straight Bath Front Panel 1800mm - Twilight Blue
87242 Old London Straight Bath Front Panel 1700mm - Timeless Sand
87243 Old London Straight Bath Front Panel 1800mm - Timeless Sand
87247 Old London Straight Bath Front Panel 1700mm - Hunter Green
87248 Old London Straight Bath Front Panel 1800mm - Hunter Green
87578 Hudson Reed Urban L-Shape Square Shower Bath Front Panel 1700mm - Satin White
87579 Hudson Reed Urban Straight Bath Front Panel 1700mm - Satin White
87580 Hudson Reed Urban Straight Bath Front Panel 1800mm - Satin White
87593 Hudson Reed Urban L-Shape Square Shower Bath Front Panel 1700mm - Satin Grey
87594 Hudson Reed Urban Straight Bath Front Panel 1700mm - Satin Grey
87595 Hudson Reed Urban Straight Bath Front Panel 1800mm - Satin Grey
87608 Hudson Reed Urban L-Shape Square Shower Bath Front Panel 1700mm - Satin Blue
87609 Hudson Reed Urban Straight Bath Front Panel 1700mm - Satin Blue
87610 Hudson Reed Urban Straight Bath Front Panel 1800mm - Satin Blue
87652 Hudson Reed 1700mm Straight Bath Front Panel & Plinth - Autumn Oak
87653 Hudson Reed 1800mm Straight Bath Front Panel & Plinth - Autumn Oak
87658 Hudson Reed 1700mm L Shape Square Shower Bath Front Panel - Autumn Oak
87666 Hudson Reed 1700mm Straight Bath Front Panel & Plinth - Graphite Grey
87667 Hudson Reed 1800mm Straight Bath Front Panel & Plinth - Graphite Grey
87672 Hudson Reed 1700mm L Shape Square Shower Bath Front Panel - Graphite Grey
87673 Hudson Reed 1700mm Straight Bath Front Panel & Plinth - Coastal Grey
87674 Hudson Reed 1800mm Straight Bath Front Panel & Plinth - Coastal Grey
87679 Hudson Reed 1700mm L Shape Square Shower Bath Front Panel - Coastal Grey
87680 Hudson Reed Havana Straight Shower Bath Front Panel & Plinth, 1700mm - Metallic Slate
87681 Hudson Reed Havana Straight Shower Bath Front Panel & Plinth, 1800mm - Metallic Slate
87686 Hudson Reed Havana Square L Shape Shower Bath Front Panel & Plinth, 1700mm - Metallic Slate
87701 nuie 1700mm Straight Front Panel & Plinth - Solace Oak Woodgrain
87702 nuie 1800mm Straight Front Panel & Plinth - Solace Oak Woodgrain
87707 nuie 1700mm L Shape Square Shower Bath Front Panel - Solace Oak Woodgrain
87710 Hudson Reed Fusion Bath Front Panel 1800mm - Anthracite Woodgrain
87711 nuie 1800mm Straight Front Panel & Plinth - Anthracite Woodgrain
87724 Hudson Reed Fusion Bath Front Panel 1800mm - Hacienda Black
87725 nuie 1800mm Straight Front Panel & Plinth - Charcoal Black Woodgrain
88151 Hudson Reed 1700mm L Shape Square Shower Bath Front Panel - Satin Anthracite
88153 Hudson Reed 1700mm L Shape Square Shower Bath Front Panel - Satin Green
88789 Hudson Reed Fusion L-Shape Shower Bath Front Panel 1700mm - Gloss Grey
88790 Hudson Reed Fusion Bath Front Panel & Plinth 1700mm - Gloss Grey
88791 Hudson Reed Fusion Bath Front Panel 1800mm - Gloss Grey
88904 nuie Shingle Back To Wall Bath Panel - White
90824 Nuie Back To Wall Corner Bath Panel - Left Hand
90825 Nuie Crescent Back To Wall Corner Bath Panel - Right Hand