It is possible to narrow down the audit log by Object and by Fields.
The Object list will contain the main item in addition to all sub-items of the main item. You can filter the audit log by selecting one or multiple items in the list.
The Field list will contain all fields that are related to the main item in addition to all fields related to all sub-items. Also here you can select one or multiple items to filter by.
When a filter is selected the filter field will show the name of the selected filter, i.e Cargo in the example above.
If multiple items are selected in any of the filters the filter field will show the name of the first selected item in addition to +number of other selected items ( Freight Rate +2 in the example above).