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, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    431380, 432643, 430955, 425786, 433168, 
    420963, 435716, 436514, 419288, 424427, 
    460521, 414020, 414696, 431630, 420330, 
    439312, 427057, 405641, 426607, 407640, 
    409611, 428383, 409077, 440298, 450604, 
    455510, 402558, 401092, 442722, 442428, 
    417957, 432262, 452815, 431646, 439685, 
    440664, 451688, 410924, 423745, 420062, 
    434608, 446159, 429578, 425486, 423026, 
    435351, 456510, 404001
  ) 
  AND cscart_product_descriptions.lang_code = 'ar'

Query time 0.00138

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.08425304,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_descriptions",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "product_id"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["product_id", "lang_code"],
          "loops": 1,
          "rows": 48,
          "cost": 0.08425304,
          "filtered": 100,
          "attached_condition": "cscart_product_descriptions.product_id in (431380,432643,430955,425786,433168,420963,435716,436514,419288,424427,460521,414020,414696,431630,420330,439312,427057,405641,426607,407640,409611,428383,409077,440298,450604,455510,402558,401092,442722,442428,417957,432262,452815,431646,439685,440664,451688,410924,423745,420062,434608,446159,429578,425486,423026,435351,456510,404001) and cscart_product_descriptions.lang_code = 'ar'"
        }
      }
    ]
  }
}