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 (
    10526, 10527, 10535, 10537, 10538, 10539, 
    10540, 10541, 10542, 10543, 10544, 
    10557, 10558, 10559, 10562, 10563
  ) 
  AND cscart_product_descriptions.lang_code = 'ru'

Query time 0.00141

JSON explain

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  "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 (10526,10527,10535,10537,10538,10539,10540,10541,10542,10543,10544,10557,10558,10559,10562,10563) and cscart_product_descriptions.lang_code = 'ru'"
    }
  }
}

Result

product_id short_description full_description unit_name
10526 Ultrasonic Sensor Assembly-Parking Assist System<p>Part number 99310L1200MDY</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10527 screw-tapping<p>Part number 1249305207B</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10535 Molding-Back Window<p>Part number 87120T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10537 screw-tapping<p>Part number 1249204107E</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10538 screw-tapping<p>Part number 1249204083</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10539 Outside handle & lock assembly-trunk lid<p>Part number 81260T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10540 Fasteners - Door Trim<p>Part number 82315T1030</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10541 Fasteners - Door Trim<p>Part number 8231527000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10542 Clip-Molding Mounting<p>Part number 873822W000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10543 Emblem-G80<p>Part number 86310T1100</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10544 Emblem-AWD<p>Part number 86316T1100</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10557 Pad-sealing<p>Part number 87325T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10558 Lamp assembly-rear combination inside, left<p>Part number 92403T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10559 Lamp assembly-rear combination inside, right<p>Part number 92404T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10562 Mirror assembly - outside rear view, left<p>Part number 87610JI010MDY</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10563 Mirror assembly - outside rear view, right<p>Part number 87620JI010MDY</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>