diff --git a/src/ngx-tree-select/src/components/tree-select.component.ts b/src/ngx-tree-select/src/components/tree-select.component.ts
index 3f13b64..9d7e2c2 100644
--- a/src/ngx-tree-select/src/components/tree-select.component.ts
+++ b/src/ngx-tree-select/src/components/tree-select.component.ts
@@ -124,6 +124,7 @@ export class TreeSelectComponent implements ControlValueAccessor {
     for (const item of this.internalItems) {
       this.ProcessMatchFilterTreeItem(item, this.svc.Configuration.filter);
     }
+    this.svc.setExpand();
   }
 
   public constructor(
@@ -268,11 +269,6 @@ export class TreeSelectComponent implements ControlValueAccessor {
                         tree.text.toLowerCase().indexOf(filter.toLowerCase()) > -1 ||
                         result
                       );
-    if (filter !== '') {
-      tree.isOpen = true;
-    } else {
-      tree.isOpen = false;
-    }
     return tree.matchFilter;
   }
 }
diff --git a/src/ngx-tree-select/src/models/select-option.ts b/src/ngx-tree-select/src/models/select-option.ts
index 259da5a..35b186d 100644
--- a/src/ngx-tree-select/src/models/select-option.ts
+++ b/src/ngx-tree-select/src/models/select-option.ts
@@ -19,6 +19,15 @@ export class SelectOption {
     return this.childProperty && this.childProperty.trim().length > 0;
   }
 
+  public get filterExpandMode(): ExpandMode
+  {
+     if (this.filter !== '') {
+        return ExpandMode.All;
+     } else {
+       return this.expandMode;
+     }
+  }
+
   public displayCheckbox(): boolean {
     return this.allowMultiple && this.isHierarchy();
   }
diff --git a/src/ngx-tree-select/src/services/select.service.ts b/src/ngx-tree-select/src/services/select.service.ts
index 14b8d8d..6ebddb0 100644
--- a/src/ngx-tree-select/src/services/select.service.ts
+++ b/src/ngx-tree-select/src/services/select.service.ts
@@ -117,17 +117,6 @@ export class SelectService {
     }
   }
 
-  public setAllOpoen(items: SelectableItem[]) {
-    for (const itm of items) {
-      if (itm.hasChild) {
-        itm.isOpen = true;
-        this.setAllOpoen(itm.children);
-      } else {
-        itm.isOpen = true;
-      }
-    }
-  }
-
   public setConfiguration(delegate: OptionDelegate, processItems: boolean): void {
     const modelBck = this._options.model;
     delegate(this._options);
@@ -151,17 +140,21 @@ export class SelectService {
   }
 
   public setExpand() {
-    if (this._items) {
-      for (const item of this._items) {
-        if (this._options.expandMode === ExpandMode.All) {
-          item.isOpen = true;
-          if (item.hasChild) {
-            this.setAllOpoen(item.children);
-          }
-        } else if (this._options.expandMode === ExpandMode.Selection && item.children) {
-          item.isOpen = item.children.some((itm: SelectableItem) => itm.isOpen || itm.selected);
-        } else {
-          item.isOpen = false;
+    this.setExpandForList(this._items);
+  }
+
+  private setExpandForList(items: SelectableItem[]) {
+    if (!items) {
+      return;
+    }
+    for (const item of items) {
+      this.setExpandForList(item.children);
+      item.isOpen = (this._options.filterExpandMode === ExpandMode.All);
+      if (this._options.filterExpandMode === ExpandMode.Selection) {
+        if (item.children) {
+          item.isOpen = item.children.some(
+            (itm: SelectableItem) => itm.isOpen || itm.selected
+          );
         }
       }
     }