Query: use "union" for complex XPath queries that use "or"

The following XPath query is converted to a union, however there is still an "or" in the converted query, which means the query still can't use all indexes and has to traverse the whole repository:

//*[(((@jcr:primaryType = 'nt:unstructured') 
and (@resources = '/data' or @resolved = '/data'))
or (@content = '/data' and (@jcr:primaryType = 'nt:folder'))) ]