SELECT 
  * 
FROM 
  cscart_mb_salvage_cases 
WHERE 
  auction_product_id IN (
    20861, 20862, 20863, 20864, 20865, 20866, 
    20867, 20868, 20869, 20870, 20871, 
    20872, 20873, 20874, 20875, 20876
  ) 
  OR sale_product_id IN (
    20861, 20862, 20863, 20864, 20865, 20866, 
    20867, 20868, 20869, 20870, 20871, 
    20872, 20873, 20874, 20875, 20876
  ) 
ORDER BY 
  updated_at DESC, 
  case_id DESC

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "read_sorted_file": {
      "filesort": {
        "sort_key": "cscart_mb_salvage_cases.updated_at desc, cscart_mb_salvage_cases.case_id desc",
        "table": {
          "table_name": "cscart_mb_salvage_cases",
          "access_type": "ALL",
          "rows": 56,
          "filtered": 100,
          "attached_condition": "cscart_mb_salvage_cases.auction_product_id in (20861,20862,20863,20864,20865,20866,20867,20868,20869,20870,20871,20872,20873,20874,20875,20876) or cscart_mb_salvage_cases.sale_product_id in (20861,20862,20863,20864,20865,20866,20867,20868,20869,20870,20871,20872,20873,20874,20875,20876)"
        }
      }
    }
  }
}