ES-978602 - Prepare UG documentation for FilterLevel Extended behavior changes in WPF SfTreeGrid

Author: GowthamabalajiSambathSF4978

wpf/TreeGrid/Filtering.md

@@ -27,7 +27,7 @@ treeGrid.FilterLevel = FilterLevel.All;
 
 * All - Filter will be applied to all the nodes in SfTreeGrid.
 
-* Extended - Filter will be applied to all the nodes. If a node matches the filter condition, its all ancestors will be displayed even though the parent node does not match the filter condition.
+* Extended - Filter will be applied to all the nodes. However, filter will be applied to child nodes only when their parent node is either in an expanded state or matches the filter condition. If a node matches the filter condition, its all ancestors will be displayed even though the parent node does not match the filter condition.
 
 **Root**
 
@@ -39,7 +39,7 @@ Filter will be applied to all the nodes in SfTreeGrid. If a parent node does not
 
 **Extended**
 
-Filter will be applied to all the nodes. If a node matches the filter condition, its all ancestors will also be displayed even though the parent node does not match the filter condition, and parent node’s `IsFiltered` value will be set to false.
+Filter will be applied to all the nodes. However, filter will be applied to child nodes only when their parent node is either in an expanded state or matches the filter condition. If a node matches the filter condition, its all ancestors will also be displayed even though the parent node does not match the filter condition, and parent node’s `IsFiltered` value will be set to false.
 
 N> You can change the `FilterLevel` at run time.