SELECT 
  product_id, 
  feature_short_desc 
FROM 
  cscart_ab__short_desc_from_features_values 
WHERE 
  product_id IN (
    276633, 276634, 276635, 276636, 276637, 
    276638, 276639, 276640, 276641, 276642, 
    276643, 276644, 276645, 276646, 276647, 
    276648, 276649, 276650, 276651, 276652, 
    276653, 276654, 276655, 276656, 276657, 
    276658, 276659, 276660, 276661, 276662
  ) 
  AND lang_code = 'en' 
  AND storefront_id = 1

Query time 0.00093

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "13.52"
    },
    "table": {
      "table_name": "cscart_ab__short_desc_from_features_values",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 30,
      "rows_produced_per_join": 3,
      "filtered": "10.00",
      "cost_info": {
        "read_cost": "13.22",
        "eval_cost": "0.30",
        "prefix_cost": "13.52",
        "data_read_per_join": "96"
      },
      "used_columns": [
        "product_id",
        "feature_short_desc",
        "lang_code",
        "storefront_id"
      ],
      "attached_condition": "((`s2cart`.`cscart_ab__short_desc_from_features_values`.`storefront_id` = 1) and (`s2cart`.`cscart_ab__short_desc_from_features_values`.`product_id` in (276633,276634,276635,276636,276637,276638,276639,276640,276641,276642,276643,276644,276645,276646,276647,276648,276649,276650,276651,276652,276653,276654,276655,276656,276657,276658,276659,276660,276661,276662)) and (`s2cart`.`cscart_ab__short_desc_from_features_values`.`lang_code` = 'en'))"
    }
  }
}