How to get Elements by multiple tag names in Xerces-C?

How to get Elements by multiple tag names in Xerces-C?

I am using Xerces C++ to create a DOMNodeList from a XMLdom like this
(this is working):
DOMNodeList * module_instance_list =
InputDom->getElementsByTagName(X("ABC_INSTANCE"));
while X being a function to convert the string into a XMLString.
I would like to get elements by two or more different tag names and put
them into a DOMNodeList like this
DOMNodeList * module_instance_list =
InputDom->getElementsByTagName(X("ABC_INSTANCE")) +
InputDom->getElementsByTagName(X("ABC"));
or something like that:
DOMNodeList * module_instance_list =
InputDom->getElementsByTagName(X("ABC_INSTANCE") or X("ABC"));
or alternatively search for all beginning with 'ABC'
DOMNodeList * module_instance_list =
InputDom->getElementsByTagName(X("ABC*"));
But this is all not working. Is there any easy way to do this?