Sorry, my English is not good, use google translate

I want to use SOLIDWORKS Document Manager to traverse the top-level combination diagram to find all related sub-components, parts, and engineering diagrams. I currently see ISwDMExternalReferenceOption Interface Properties and I have done relevant examples to find sub-components and parts, but there is no way to find the project. For the file information of the picture, I have tried to use SearchFilters and given the SwDmSearchForDrawing constant, but I still cannot successfully fetch the engineering drawing related data during the traversal process. I don't know what I am wrong?

SwDmSearchFilters Enumeration