If you are talking about combining multiple charts from several different QVW files in a central dashboard, Your basic options are still the same in QV 10 as they were in 9.
1) Recommended - Create an entirely separate QVW that holds just enough summarized information to draw the individual charts you want. Use document chaining to open the other documents as needed for more detailed analysis.
2) Not Generally Recommended - Use the QlikView Workbench to create a webpage that actually shows the charts from the separate QVWs in one dashboard. Note, that displaying this dashboard will actually result in opening (and loading into memory) ALL of the QVWs that have a chart on the dashboard. This is a fairly inefficient use of RAM and that is why this method is not generally recommended.