SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '', 
    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 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    6313, 6312, 6315, 6237, 6308, 6314, 6307, 
    6309, 6311, 6310
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "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": 10,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (6313,6312,6315,6237,6308,6314,6307,6309,6311,6310)",
      "attached_condition": "cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text
6237 <p> /Tri-band base antenna with coupler - 150-174 / 380-512 & 760-896 MHz</p>
6307 <p>Quad band base antenna with coupler for above plus 106-130 MHz</p>
6308 <p>Interoperable antenna only 106-1550 MHz</p>
6309
6310 <p>Optional black Storm case</p>
6311
6312 <p>Optional multi band coupler - 106-130 / 150-174 / 380-512 / 760-896 MHz</p>
6313 <p>Complete Ground Plane Kit System with Storm Case</p>
6314 <p>Storm case with custom foam for GPK</p>
6315 <p>Custom ground plane kit with radials</p>