diff --git a/component/domain-trie/tire.go b/component/domain-trie/tire.go
index 8d570214..13567a98 100644
--- a/component/domain-trie/tire.go
+++ b/component/domain-trie/tire.go
@@ -75,6 +75,10 @@ func (t *Trie) Search(domain string) *Node {
 		n = child
 	}
 
+	if n.Data == nil {
+		return nil
+	}
+
 	return n
 }
 
diff --git a/component/domain-trie/trie_test.go b/component/domain-trie/trie_test.go
index cd80ce3d..bd594e97 100644
--- a/component/domain-trie/trie_test.go
+++ b/component/domain-trie/trie_test.go
@@ -5,6 +5,8 @@ import (
 	"testing"
 )
 
+var localIP = net.IP{127, 0, 0, 1}
+
 func TestTrie_Basic(t *testing.T) {
 	tree := New()
 	domains := []string{
@@ -13,7 +15,7 @@ func TestTrie_Basic(t *testing.T) {
 	}
 
 	for _, domain := range domains {
-		tree.Insert(domain, net.ParseIP("127.0.0.1"))
+		tree.Insert(domain, localIP)
 	}
 
 	node := tree.Search("example.com")
@@ -21,7 +23,7 @@ func TestTrie_Basic(t *testing.T) {
 		t.Error("should not recv nil")
 	}
 
-	if !node.Data.(net.IP).Equal(net.IP{127, 0, 0, 1}) {
+	if !node.Data.(net.IP).Equal(localIP) {
 		t.Error("should equal 127.0.0.1")
 	}
 }
@@ -35,7 +37,7 @@ func TestTrie_Wildcard(t *testing.T) {
 	}
 
 	for _, domain := range domains {
-		tree.Insert(domain, nil)
+		tree.Insert(domain, localIP)
 	}
 
 	if tree.Search("sub.example.com") == nil {
@@ -53,13 +55,17 @@ func TestTrie_Wildcard(t *testing.T) {
 	if tree.Search("foo.example.dev") != nil {
 		t.Error("should recv nil")
 	}
+
+	if tree.Search("example.com") != nil {
+		t.Error("should recv nil")
+	}
 }
 
 func TestTrie_Boundary(t *testing.T) {
 	tree := New()
-	tree.Insert("*.dev", nil)
+	tree.Insert("*.dev", localIP)
 
-	if err := tree.Insert("com", nil); err == nil {
+	if err := tree.Insert("com", localIP); err == nil {
 		t.Error("should recv err")
 	}