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 (
    19581, 19582, 19583, 19584, 19585, 19586, 
    19587, 19588, 19589, 19590, 19591, 
    19592, 19593, 19594, 19595, 19596
  ) 
  AND cscart_product_descriptions.lang_code = 'ru'

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "product_id", "idx_product_lang"],
      "key": "PRIMARY",
      "key_length": "9",
      "used_key_parts": ["product_id", "lang_code"],
      "rows": 16,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (19581,19582,19583,19584,19585,19586,19587,19588,19589,19590,19591,19592,19593,19594,19595,19596) and cscart_product_descriptions.lang_code = 'ru'"
    }
  }
}

Result

product_id short_description full_description unit_name
19581 Molding - rear bumper, center<p>Part number 86696G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19582 Cover Assembly - Rear Bumper Under<p>Part number 86690G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19583 Wiring Harness-Rear Bumper<p>Part number 91885G9620</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19584 Lamp assembly - back up, left<p>Part number 924A3G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19585 Lamp assembly - back up, right<p>Part number 924A4G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19586 Camera assembly - back view<p>Part number 99240G9600</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19587 Pad-windshield glass<p>Part number 86114G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19588 Glass assembly-rear window<p>Part number 86110G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19589 Glass Assembly-Tailgate<p>Part number 87160G9600</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19590 Stopper-rear window glass<p>Part number 87115A7000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19591 Stopper-rear window glass<p>Part number 87115G5000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19592 Spoiler Assy-Rear<p>Part number 87210G9500NCM</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19593 Cover - rear spoiler side, left<p>Part number 87227G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19594 Cover - rear spoiler side, right<p>Part number 87228G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19595 Lamp Assembly - High Mounted Stop<p>Part number 92700G9500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
19596 Nozzle Assembly-Rear Washer<p>Part number 98931C5000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>