SELECT 
  cscart_june_setupproduct_descriptions.product_id, 
  cscart_june_setupproduct_descriptions.short_description, 
  IF(
    cscart_june_setupproduct_descriptions.short_description = '' 
    OR cscart_june_setupproduct_descriptions.short_description IS NULL, 
    cscart_june_setupproduct_descriptions.full_description, 
    ''
  ) AS full_description, 
  cscart_june_setupproduct_descriptions.unit_name 
FROM 
  cscart_june_setupproduct_descriptions 
WHERE 
  cscart_june_setupproduct_descriptions.product_id IN (
    12, 148, 128, 160, 34, 171, 282, 46, 45, 
    44, 178
  ) 
  AND cscart_june_setupproduct_descriptions.lang_code = 'ar'

Query time 0.00066

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "26.41"
    },
    "table": {
      "table_name": "cscart_june_setupproduct_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": 11,
      "rows_produced_per_join": 11,
      "filtered": "100.00",
      "index_condition": "((`vishalecarter_june_setup`.`cscart_june_setupproduct_descriptions`.`product_id` in (12,148,128,160,34,171,282,46,45,44,178)) and (`vishalecarter_june_setup`.`cscart_june_setupproduct_descriptions`.`lang_code` = 'ar'))",
      "cost_info": {
        "read_cost": "24.21",
        "eval_cost": "2.20",
        "prefix_cost": "26.41",
        "data_read_per_join": "50K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description",
        "unit_name"
      ]
    }
  }
}