You will be able to filter the orders according to the desired fields.
Search by status (ie. approved, invoiced)
Check from creation date (ie 2017-01-01to2017-02-01)
Check from update date. (ie 2020-01-01to2021-02-01)
Search orders that contains this sku
Search by original channel id (ie 1231)
Search by channel name (ie. Mercadolivre)
Search by attribute code or attribute value field (exact)
Search by invoice number
See if has invoice number
Search by track code
Search by shipping company
Search by your application id
Show olders that is or not know (ie. ack=1 or ack=0)
you can search by any other api propriety, like "receiver_name=Anny or status=active"