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 (
    20093, 20094, 20095, 20096, 20097, 20098, 
    20099, 20100, 20101, 20102, 20103, 
    20104, 20105, 20106, 20107, 20108
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00043

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 (20093,20094,20095,20096,20097,20098,20099,20100,20101,20102,20103,20104,20105,20106,20107,20108) and cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description unit_name
20093 Motor Assembly - Steering Wheel Haptics<p>Part number 56184T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20094 Switch assembly - paddle shifters, left<p>Part number 96770T1000VCS</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20095 Switch assembly - paddle shifters, right<p>Part number 96780T1000VCS</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20096 Joint assembly - steering<p>Part number 56400T1100</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20097 Joint Assembly - Universal<p>Part number 56400T1500</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20098 Unit Assembly - TILT & TELE<p>Part number 95490T1011</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20099 Module assembly - steering wheel airbag<p>Part number 80100T1000OWN</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20100 Airbag Assembly - Passenger Seat<p>Part number 80310T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20101 Curtain airbag module, left<p>Part number 80410T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20102 Curtain airbag module, right<p>Part number 80420T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20103 Module Assy-Knee Airbag<p>Part number 80200T1100</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20104 Flange Nut - Self Locking<p>Part number 545592E000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20105 Gear & Linkage Assemblies - MDPS<p>Part number 57700T1400</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20106 Pad Kit - Front Disc Brake<p>Part number 58101T1A21</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20107 Brake Assembly-Front.Left<p>Part number 58110T1210CA</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
20108 Brake assembly - front, right<p>Part number 58130T1210CA</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>