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 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (270188, 285000) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00076

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "2.81"
    },
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 2,
      "rows_produced_per_join": 2,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "2.41",
        "eval_cost": "0.40",
        "prefix_cost": "2.81",
        "data_read_per_join": "13K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`webmarco`.`cscart_product_descriptions`.`product_id` in (270188,285000)) and (`webmarco`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
270188 <h3 class="text-center">Dacia Logan</h3> <h3><em>Garantie 100 euro</em> </h3> <h4> Classa family</h4> <ol><li>3 zile                 <strong> 22  </strong>    Euro                        </li><li>4-8 zile               <strong>21</strong>      Euro                     </li><li>9-14 zile         <strong>   19.00</strong>  Euro     </li><li>15-21 zile          <strong>16.00</strong>  Euro     </li><li>22-30 zile         <strong> 15.00</strong>  Euro    </li></ol> <h5><em>Cutie Viteza Manuala</em></h5> <h5><em>Capacitate 5 pasageri </em></h5> <h5><em>Carburant Diesel </em></h5> <h5><em>Consum Carburant 5.5 L / 100 km </em></h5> <h5><em>Ac, Abc, Airbags, Central locking, Cruise control, Electric windows, Esp</em></h5> <p><br /></p> <p><br /></p> <p><br /></p>
285000 <p>Our products are made of cotton fabrics that do not contain carcinogenic substances that attach great importance to the skin of our babies and do not cause allergic reactions.</p> <p>Some of the main benefits of cotton are its ability to soften over time while remaining stable. High-quality cotton is inevitably softer and has good insulation properties. It is valued for its ability to maintain freshness in the summer months and retain warmth in cold weather. In addition, it is also more environmentally friendly. It is also anti-allergic, which means it is good for people suffering from allergies, for example, asthma.  Cotton also has great moisture absorption for sweat or water, when washing does not break down the fibers.</p> <p><strong>Sizes:</strong></p> <ul><li>80cm /12-18 (Months)</li><li>86cm /18-24 (Months) – 1/2(Years)</li><li>92cm /24-36 (Months) – 2/3(Years)</li><li>98cm /36-48 (Months) – 3/4(Years)</li></ul>