SELECT 
  object_id 
FROM 
  cscart_profile_field_descriptions 
WHERE 
  object_type = 'F' 
  AND description = 'Is Expert'

Query time 0.00076

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "25.30"
    },
    "table": {
      "table_name": "cscart_profile_field_descriptions",
      "access_type": "ALL",
      "rows_examined_per_scan": 244,
      "rows_produced_per_join": 2,
      "filtered": "1.00",
      "cost_info": {
        "read_cost": "25.06",
        "eval_cost": "0.24",
        "prefix_cost": "25.30",
        "data_read_per_join": "1K"
      },
      "used_columns": [
        "object_id",
        "description",
        "object_type"
      ],
      "attached_condition": "((`cscart_db`.`cscart_profile_field_descriptions`.`object_type` = 'F') and (`cscart_db`.`cscart_profile_field_descriptions`.`description` = 'Is Expert'))"
    }
  }
}