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 (3988, 3987) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00021

JSON explain

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    "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": 2,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (3988,3987)",
      "attached_condition": "cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id short_description full_description meta_keywords meta_description search_words promo_text
3987 <p> This 7-inch1/2 wave whip antenna has a one-piece finish, steel core and spiral wound conductor for optimal radiation characteristics. It works in the 896-941 MHz range. Compatible with the DTR series and MTX series portables.</p> DTR650 Antenna, MTX antenna, MTX series antenna
3988 <p>This is an 806-941 MHz, 4-inch ΒΌ wave stubby antenna. It is ideal when the radio is worn on a belt because the short antenna is non-obtrusive. This broadband antenna can be used for both 800 and 900 MHz applications. </p> DTR650 Antenna