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 (
    93877, 93878, 93879, 93880, 93881, 94034, 
    94035, 94036, 94037, 94038, 94039, 
    94040, 94041, 94042, 94043, 94044, 
    94045, 94046, 94047, 94048, 94049, 
    94050, 94051, 94052, 94053, 94054, 
    94055, 94056, 94057, 94058, 94059, 
    94060, 94061, 94062, 94063, 94161, 
    94162, 94163, 94164, 94333, 94334, 
    94335, 94336, 94337, 94338, 94339, 
    94340, 94341
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00121

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 (93877,93878,93879,93880,93881,94034,94035,94036,94037,94038,94039,94040,94041,94042,94043,94044,94045,94046,94047,94048,94049,94050,94051,94052,94053,94054,94055,94056,94057,94058,94059,94060,94061,94062,94063,94161,94162,94163,94164,94333,94334,94335,94336,94337,94338,94339,94340,94341)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
93877
93878
93879
93880
93881
94034
94035
94036
94037
94038
94039
94040
94041
94042
94043
94044
94045
94046
94047
94048
94049
94050
94051
94052
94053
94054
94055
94056
94057
94058
94059
94060
94061
94062
94063
94161
94162
94163
94164
94333
94334
94335
94336
94337
94338
94339
94340
94341