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 (
    98079, 98080, 98081, 98082, 98083, 98149, 
    98150, 98153, 98156, 98176, 98177, 
    98178, 98179, 98180, 98181, 98182, 
    98183, 98184, 98185, 98186, 98187, 
    98188, 98189, 98190, 98191, 98192, 
    98193, 98194, 98195, 98196, 98197, 
    98198, 98199, 98200, 98201, 98202, 
    98203, 98204, 98205, 98206, 98207, 
    98208, 98209, 98210, 98211, 98212, 
    98213, 98214
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00098

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "26.34"
    },
    "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": "21.54",
        "eval_cost": "4.80",
        "prefix_cost": "26.34",
        "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 (98079,98080,98081,98082,98083,98149,98150,98153,98156,98176,98177,98178,98179,98180,98181,98182,98183,98184,98185,98186,98187,98188,98189,98190,98191,98192,98193,98194,98195,98196,98197,98198,98199,98200,98201,98202,98203,98204,98205,98206,98207,98208,98209,98210,98211,98212,98213,98214)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
98079
98080
98081
98082
98083
98149
98150
98153
98156
98176
98177
98178
98179
98180
98181
98182
98183
98184
98185
98186
98187
98188
98189
98190
98191
98192
98193
98194
98195
98196
98197
98198
98199
98200
98201
98202
98203
98204
98205
98206
98207
98208
98209
98210
98211
98212
98213
98214