@huulong: Why recreate the wheel when it is always invented? Or the pencils?
Have you tried the pencils from @RamonM’s Sketching-Bundles, these are great, maybe they are what you are after?
Or maybe the Jarry H. Line Brush Set for KRITA? This came just into my mind because of its ‘‘c) Pencil-1 Hard Copy’’, it is an excellent set, but it is not all pencils →
Michelist
Add/Edit: Download link renewed (1166 downloads so far. Thank you for downloading! 
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