How to filter multitable tree or treegrid

Thank you for the very nice product, am considering to get a professional version.
One of the requirements in my project is to be able to filter a tree or treegrid created from several mysql tables, e.g. header>subheader>section>code,description.
The tree is working fine but it is not clear how can the filtering be done, would appreciate your advice on that.

Unfortunately the filtering in a tree is not supported officially.

To filter the treeGrid you need to add dhtmlxtreegrid_filter.js.
Also you will need to use filterTreeBy(column, value, preserve) method.