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.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (53, 52) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_descriptions",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "product_id"],
          "key": "product_id",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "rows": 2,
          "filtered": 100,
          "index_condition": "cscart_product_descriptions.product_id in (53,52)",
          "attached_condition": "cscart_product_descriptions.lang_code = 'en'"
        }
      }
    ]
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text unit_name
52 <p>1200W Peak Power<br /> 400W RMS Power<br /> 4 ohms Impedance<br /> 34Hz - 300Hz Frequency Response<br /> 6" Mounting Depth<br /> PP Cone with Diamond Array Pattern<br /> Dual-Ventilation System<br /> Rubber Surround</p> <p class="product-promo-text"><span class="product-promo-header">FREE US shipping over $100!</span><span class="product-promo-body">Orders within next 2 days will be shipped on Monday</span></p>
53 <p>Super-sturdy, super powerful, the KFC-W3012 is a 12-inch, 4-ohm sub that handles an impressive 1200W of power. A truly high-performance sub, the KFC-W3012 has a long stroke design and a silver textured pattern cone woofer that adds strength and rigidity to the cone for maximum bass performance.</p> <p class="product-promo-text"><span class="product-promo-header">FREE US shipping over $100!</span><span class="product-promo-body">Orders within next 2 days will be shipped on Monday</span></p>