SELECT 
  product_descriptions.product_id, 
  product_descriptions.short_description, 
  IF(
    product_descriptions.short_description = '' 
    OR product_descriptions.short_description IS NULL, 
    product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  product_descriptions 
WHERE 
  product_descriptions.product_id IN (99544, 99526, 99525, 99551) 
  AND product_descriptions.lang_code = 'en'

Query time 0.00065

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "3.36"
    },
    "table": {
      "table_name": "product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "11",
      "rows_examined_per_scan": 4,
      "rows_produced_per_join": 4,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "2.97",
        "eval_cost": "0.40",
        "prefix_cost": "3.37",
        "data_read_per_join": "20K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`goimagine`.`product_descriptions`.`product_id` in (99544,99526,99525,99551)) and (`goimagine`.`product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
99525 <p>Sweet, Tangy, and cute handmade soap. Not only is this soap look and smell delicious, but it has great skin healing properties.</p> <p><br></p> <p>Packed with vitamin E, C and A. This soap keeps your skin moisturized while clean. Helps aid aging skin, eczema, dry skin, and repairs.</p> <p><br></p> <p>This fun soap features a plastic straw(only for aesthetics), lemon wedges, and ice cubes all made from soap. ***Remove straw before use.</p> <p>This is a 4-5oz bar of soap.</p> <p>Main Ingredients: Goat milk, glycerin, coconut oil, vitamin e, mica, and fragrance.&nbsp; Full list on product.</p>
99526 <p>This handmade Royal soap smells of berry patches and features a pretty swirl of colors.</p><p>It packs a whollop of skin loving ingredients that not only clean your skin but leave you moisturized.</p><p>Main Ingredients: Goat Milk, honey, coconut oil, Vitamin E, mica and fragrance. Full list on product.</p>
99544 <p>This handmade soap is full of moisturizing properties that repair and rejuvenate the skin.</p><p>Made with real Goat Milk and local Honey.</p><p><br></p><p>Main Ingredients: Goat Milk, Honey, coconut oil, Vitamin E, Fragrance, and Mica. *Full list of ingredients on product.</p><p>These are 4-5oz bars.</p>
99551 <p>This handmade soap not only cleans but the smell is mouth watering.</p> <p><br></p> <p>Its full of goodness in the form of coconut oil, and Vitamin E.&nbsp;</p> <p><br></p> <p>This soap is layered fun,&nbsp; Resembling a watermelon. On top and throughout are clay watermelons for decoration.&nbsp;</p> <p>Main Ingredients: Glycerin, Honey, coconut oil, fragrance, and mica.</p>