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 (
    17, 180, 18, 16, 4, 5, 23, 24, 1, 22, 149, 
    190, 189, 3438, 3439, 3440, 3441, 121590, 
    136148, 156245, 169350, 125861, 122330, 
    152282, 146567, 139654, 133778, 149640, 
    159133, 146242, 165619, 121896, 143574, 
    121541, 161803, 151867, 130403, 144684, 
    120464, 144963, 125358, 157738, 154235, 
    137235, 157361, 133193, 157759, 159140, 
    166388, 176206, 135170, 128666, 120703, 
    142104, 162657, 128639, 137145, 145590, 
    160493, 159086, 144380, 153320, 171492, 
    156206
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00420

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.11207368,
    "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": 64,
          "cost": 0.11207368,
          "filtered": 100,
          "attached_condition": "cscart_product_descriptions.product_id in (17,180,18,16,4,5,23,24,1,22,149,190,189,3438,3439,3440,3441,121590,136148,156245,169350,125861,122330,152282,146567,139654,133778,149640,159133,146242,165619,121896,143574,121541,161803,151867,130403,144684,120464,144963,125358,157738,154235,137235,157361,133193,157759,159140,166388,176206,135170,128666,120703,142104,162657,128639,137145,145590,160493,159086,144380,153320,171492,156206) and cscart_product_descriptions.lang_code = 'en'"
        }
      }
    ]
  }
}