You want to sort items by using more than one parameter.
SAP Business ByDesign HTML5 layout
This is a missing functionality in HTML5 1711 systems and older.
The functionality has been added with the 1802 release and now fully mirrors the Silverlight function.
multi column sorting; sorting; personalization; overview; owl; , KBA , multi column sorting , sorting , personalization , overview , owl , AP-RC-UIF-RT-B , ByD HTML5 Client (not for Cloud for Customer) , Problem
SAP Business ByDesign 1802