Hello Vladimir.
 
 I think is it better for dividing the blocks by their type?
 ex: *.ipt to be in Inventor directory ,  *.dwg to be in AutoCAD directory
 
 just a mention. 

Thanks for your input.
 
In fact the Catalog contents is not divided into directories - it is just a database. But you can filter the files (blocks) in a specified format only - see the links on the left or in the heading: DWG, IPT, RFA. You can also select a specific format only (i.e. DWG20004) on the advanced search page.