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.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (6870, 6869, 6876, 6871) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "2.84"
    },
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 4,
      "rows_produced_per_join": 4,
      "filtered": "100.00",
      "index_condition": "((`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_descriptions`.`product_id` in (6870,6869,6876,6871)) and (`softwarepirmam_hewadelivard_cscart_4`.`cscart_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "2.44",
        "eval_cost": "0.40",
        "prefix_cost": "2.84",
        "data_read_per_join": "18K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description",
        "unit_name"
      ]
    }
  }
}

Result

product_id short_description full_description unit_name
6869 <p>Huda Beauty Faux Filler Gloss delivers a plump, glossy finish that instantly enhances the lips. Its lightweight, non sticky formula glides smoothly for all day comfort and shine. Infused with nourishing ingredients, it keeps lips hydrated and soft. Perfect for achieving a luscious, full lip look with a touch of effortless glamour.</p>
6870 <p>Huda Beauty Blush Filter – Ube Cream provides a natural, radiant flush that enhances your cheeks with a soft, buildable color. Its lightweight, creamy formula blends effortlessly for a seamless, airbrushed finish. Infused with nourishing ingredients, it keeps skin feeling smooth and hydrated. Perfect for layering or wearing alone for a subtle, glowing look. Ideal for all skin tones, it adds a touch of luminous warmth to any makeup look.</p>
6871 <p>Huda Beauty Easy Bake Setting Spray 100ml locks makeup in place for a long lasting, flawless finish. Its lightweight formula refreshes and hydrates the skin without feeling heavy or sticky. Infused with nourishing ingredients, it helps maintain a smooth, radiant look throughout the day. Perfect for setting makeup or giving a quick refresh for a natural, dewy glow.</p>
6876 <p>Huda Beauty Easy Blur Primer creates a smooth, flawless base for makeup application. Its lightweight, silky formula blurs imperfections and minimizes the appearance of pores. Infused with hydrating ingredients, it keeps skin soft and comfortable all day. Perfect for achieving a long lasting, airbrushed finish with a natural glow.</p>