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 (
    95843, 95844, 95845, 95846, 95847, 95848, 
    95849, 95850, 95851, 95852, 95853, 
    95854, 95855, 95856, 95857, 95858, 
    95859, 95860, 95861, 95862, 95863, 
    95864, 95865, 95866, 95885, 95886, 
    95887, 95888, 95894, 96117
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "13.52"
    },
    "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": 30,
      "rows_produced_per_join": 30,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "10.52",
        "eval_cost": "3.00",
        "prefix_cost": "13.52",
        "data_read_per_join": "114K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (95843,95844,95845,95846,95847,95848,95849,95850,95851,95852,95853,95854,95855,95856,95857,95858,95859,95860,95861,95862,95863,95864,95865,95866,95885,95886,95887,95888,95894,96117)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
95843
95844
95845
95846
95847
95848
95849
95850
95851
95852
95853
95854
95855
95856
95857
95858
95859
95860
95861
95862
95863
95864
95865
95866
95885
95886
95887
95888
95894
96117