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 (
    93754, 93755, 93756, 93757, 93758, 93759, 
    93760, 93761, 93762, 93763, 93764, 
    93765, 93766, 93767, 93768, 93769, 
    93770, 93771, 93772, 93773, 93774, 
    93775, 93776, 93777, 93778, 93779, 
    93780, 93790, 93791, 93825
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00076

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 (93754,93755,93756,93757,93758,93759,93760,93761,93762,93763,93764,93765,93766,93767,93768,93769,93770,93771,93772,93773,93774,93775,93776,93777,93778,93779,93780,93790,93791,93825)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
93754
93755
93756
93757
93758
93759
93760
93761
93762
93763
93764
93765
93766
93767
93768
93769
93770
93771
93772
93773
93774
93775
93776
93777
93778
93779
93780
93790
93791
93825