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 (951, 6190, 6895) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00020

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": 3,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (951,6190,6895)",
      "attached_condition": "cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text
951 <ul><li>5G IMPACT RATING</li><li>IP54 RATING ENSURES RESISTANCE AGAINST DUST AND LIQUID</li><li>INTEGRATED CONTROL BOX ENSURES CLEAN AND EASY INSTALLATION</li><li>PARKING DISTANCE GRID LINES HELP GUIDE BACKING MANEUVERS</li><li>ONE SENSOR AUTOMATICALLY TRIGGERS THE DISPLAY OF YOUR MOST CRITICAL BLIND SPOT</li><li>DISPLAY RESOLUTION: 480 X 234</li><li>THE 70RP MONITOR SUPPORTS ONLY 1 CAMERA</li><li>COMPATIBLE WITH VARIOUS TYPES OF CAMERAS - 630A, 622 SERIES, SV-EXTCAM, 690H.</li></ul> backup camera system, back up camera system, back-up camera system, back-up camera
6190 <p>Costar Mobile Video - 2MP 7" rear vision camera system includes: 7" high resolution 2CH LCD monitor with audio, 1080p AHD 2.8mm rugged weather resistant (IP-66) camera, up to 32' camera cable</p>
6895 <p>Designed for large vehicles such as fire trucks, this 3-camera system includes a 4 input 7" LED monitor, 2 side mounted cameras and 1 rear vision (back-up) camera. Also includes (2) 32' camera cables for the side mounted cameras and (1) 65' camera cable for the rear vision camera.</p> backup camera, back up camera, backup camera system, back up camera system, back-up camera, back-up camera system, backup camera system