parent category filter in categories manager

[Daroch]

Hi all,
I'm working in a project with Joomla 2.5.24 and Virtuemart 2.6.6
The shop have a lot of categories (400) with similar names and is difficult to manage these categories. The search filter in very useful but I'm trying to add a filter parent category too.
Similar to parent category filter in products manager.
I have copied the category tree select from products manager, but i don´t know how to modify the "search" function to pass the variable and restrict the categories shown.
It is possible?
Thanks in advance