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 (
    5584, 5481, 5489, 5428, 5524, 5591, 5511, 
    5419, 5495, 5423, 5424, 5480, 5486, 
    5657, 5546, 5543, 5440, 5547, 9547, 
    5438, 5443, 5476, 5542, 5548, 5592, 
    5585, 5649, 5447, 5529, 5439, 5659, 
    5602, 5496, 5656, 5475, 5433, 5498, 
    5603, 5432, 5514
  ) 
  AND cscart_product_descriptions.lang_code = 'ar'

Query time 0.00141

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "28.33"
    },
    "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": 40,
      "rows_produced_per_join": 40,
      "filtered": "100.00",
      "index_condition": "((`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_descriptions`.`product_id` in (5584,5481,5489,5428,5524,5591,5511,5419,5495,5423,5424,5480,5486,5657,5546,5543,5440,5547,9547,5438,5443,5476,5542,5548,5592,5585,5649,5447,5529,5439,5659,5602,5496,5656,5475,5433,5498,5603,5432,5514)) and (`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_descriptions`.`lang_code` = 'ar'))",
      "cost_info": {
        "read_cost": "24.33",
        "eval_cost": "4.00",
        "prefix_cost": "28.33",
        "data_read_per_join": "182K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description",
        "unit_name"
      ]
    }
  }
}