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 (
    10127, 10128, 10129, 10145, 10160, 10166, 
    10167, 10170, 10171, 10172, 10173, 
    10174, 10175, 10176, 10177, 10178
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00042

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 (10127,10128,10129,10145,10160,10166,10167,10170,10171,10172,10173,10174,10175,10176,10177,10178) and cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description unit_name
10127 coil spring<p>Part number 858313K010</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10128 Hook Assembly - Coat<p>Part number 85838B1600</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10129 Clip-Trim Mounting<p>Part number 85858T6000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10145 Trim assembly - front door scuff, right<p>Part number 85880T6000UBL</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10160 deflector pivot<p>Part number 81681D8000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10166 Tilt lever - panoramic roof moving glass, left<p>Part number 81635J7000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10167 Tilt lever-panoramic roof moving glass, right<p>Part number 81636J7000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10170 Weather strip - front door body side, left<p>Part number 82110T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10171 Weather strip - front door body side, right<p>Part number 82120T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10172 Weather strip assembly - front door lower, left<p>Part number 82170T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10173 Weather strip assembly - front door side, left<p>Part number 82130T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10174 Weather strip assembly-front door lower, right<p>Part number 82180T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10175 Weather strip assembly - front door side, right<p>Part number 82140T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10176 Weather strip assembly-front door parting, left<p>Part number 821A0T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10177 Weather strip assembly-front door parting, right<p>Part number 821B0T1000</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>
10178 Weather strip - front door belt outside, left<p>Part number 82210T1001</p><p>If you are not sure about compatibility, please contact us in advance to confirm the part number.</p>