I'd suggest you use a flowchart (or charts)to map your documentation system. For ideas take a look at the "maps" section on this site.

There's a question in http://Elsmar.com/level2/doc-hier.html
"Is This Your Company's Documentation Pyramid?"

Yes, but we have too much documents and there're lot of relations therefore I'd like a graphic-showing for better follow-up

Please give me an idea how can do it!

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