SELECT 
  * 
FROM 
  cscart_mb_salvage_cases 
WHERE 
  auction_product_id IN (
    20669, 20670, 20671, 20672, 20673, 20674, 
    20675, 20676, 20677, 20678, 20679, 
    20680, 20681, 20682, 20683, 20684
  ) 
  OR sale_product_id IN (
    20669, 20670, 20671, 20672, 20673, 20674, 
    20675, 20676, 20677, 20678, 20679, 
    20680, 20681, 20682, 20683, 20684
  ) 
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 (20669,20670,20671,20672,20673,20674,20675,20676,20677,20678,20679,20680,20681,20682,20683,20684) or cscart_mb_salvage_cases.sale_product_id in (20669,20670,20671,20672,20673,20674,20675,20676,20677,20678,20679,20680,20681,20682,20683,20684)"
        }
      }
    }
  }
}