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 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    297, 296, 295, 294, 293, 292, 291, 290, 
    289, 288, 286, 285
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00054

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "ALL",
      "possible_keys": ["PRIMARY", "product_id"],
      "rows": 12,
      "filtered": 100,
      "attached_condition": "((cscart_product_descriptions.product_id in (297,296,295,294,293,292,291,290,289,288,286,285)) and (cscart_product_descriptions.lang_code = 'en'))"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text
285 <p><b>Holden</b>: Captiva SUV</p> <p><b>Model</b>&nbsp;:</p> <p><b>Year</b>: December 07</p> <p><b>Colour</b>: Silver&nbsp;</p> <p><b>Paint</b>&nbsp;Code:</p> <p><b>Motor</b>:</p> <p><b>Millage</b>: 185694 km</p> <p><b>Vehicle Damage</b></p> <p>Slight front Right</p> HOLDEN CAPTIVA SILVER SUV 07 WRECKING HOLDEN CAPTIVA SILVER SUV 07 WRECKING captiva, silver, 2007, holden
286 HONDA, HONDA CIVIC, CIVIC, 98 HONDA CIVIC
288 <p></p><p>2005 HOLDEN ADVENTRA</p> <p>AUTO V6 260,433kms</p> VZ,ADVENTRA,HOLDEN
289 <p>Wrecking 1999 Ford AU XR6</p><p>6cyl Auto</p> Ford,Xr6
290 <p>2012 Holden Captiva V6 Auto</p> Holden,Captiva,Black
291 <p>2006 Mitsubishi Lancer CS 4cyl Manual</p> 2006,Mitsubishi,Lancer, CS, 4cyl ,Manual
292 <p>2007 Nissan Navara D40 Turbo Diesel Auto 253,793kms</p> 2007, Nissan ,Navara ,D40, Turbo, Diesel ,Auto
293 <p>Wrecking 2003 Mitsubishi Magna TL V6 Auto 228,791kms</p> 2003 ,Mitsubishi, Magna, TL, V6, Auto
294 2013 ,Ford ,Focus ,Petrol ,Manual
295 <p>Wrecking&nbsp;1992 Holden Rodeo 4cyl Petrol Auto 357,626kms</p> Rodeo, White rodeo, wrecking white holden rodeo, ​Wrecking 1992 Holden, Rodeo,4cyl,Petrol,Auto
296 <p>2010 Nissan X-Trail Turbo Diesel Auto</p><p>300,861kms</p> Nissan,X-Trail,Turbo,Diesel,Auto
297 <p>1994 Hyundai Excel Single Cam Auto 249436kms</p> Hyundai,Excel