diff --git a/core/filter.cpp b/core/filter.cpp
index 5d254f69..f39c3ebe 100644
--- a/core/filter.cpp
+++ b/core/filter.cpp
@@ -36,26 +36,28 @@ void filter_add(const gchar *text, unsigned int index)
 	}
 }
 
-void filter :: search(const std::string &text, struct set *res)
+void filter_search(const gchar *text, struct set *res)
 {
-	gchar *g_lc = string_lowercase(text.c_str());
-	const std::string lc = g_lc;
-	size_t begin = 0, end;
-	index_entry *found;
+	gchar *lower = string_lowercase(text);
+	struct index_entry *found;
+	glong begin, end;
+	gchar *c, *substr;
 
-	g_free(g_lc);
 	set_clear(res);
+	c = lower;
 
-	for (end = 1; end <= lc.size(); end++) {
-		end = lc.find(' ', begin);
-		if (end == std::string::npos)
-			end = lc.size();
+	for (begin = 0, end = 1; end <= g_utf8_strlen(lower, -1); end++) {
+		c = g_utf8_next_char(c);
+		if ((*c != '\0') && !g_unichar_isspace(g_utf8_get_char(c)))
+			continue;
+
+		substr = g_utf8_substring(lower, begin, end);
+		found  = INDEX_ENTRY(db_get(&filter_index, substr));
+		g_free(substr);
 
-		found = INDEX_ENTRY(db_get(&filter_index,
-				    lc.substr(begin, end- begin).c_str()));
 		if (!found) {
 			set_clear(res);
-			return;
+			break;
 		}
 
 		if (begin == 0)
@@ -63,6 +65,9 @@ void filter :: search(const std::string &text, struct set *res)
 		else
 			set_inline_intersect(&found->ie_set, res);
 
+		c = g_utf8_next_char(c);
 		begin = ++end;
 	}
+
+	g_free(lower);
 }
diff --git a/gui/queue/window.cpp b/gui/queue/window.cpp
index 576316cc..2e3786ee 100644
--- a/gui/queue/window.cpp
+++ b/gui/queue/window.cpp
@@ -36,7 +36,7 @@ void QueueWindow :: filter(std::string &text)
 {
 	_q_search_empty = (text.find_first_not_of(" \t") == std::string::npos);
 	if (!_q_search_empty)
-		filter :: search(text, &_q_search_res);
+		filter_search(text.c_str(), &_q_search_res);
 	q_filter->refilter();
 }
 
diff --git a/include/core/filter.h b/include/core/filter.h
index 7a722fd1..78d8ce8c 100644
--- a/include/core/filter.h
+++ b/include/core/filter.h
@@ -23,17 +23,6 @@ extern "C" {
  */
 namespace filter {
 
-	/**
-	 * Break the input text into lowercase words and search the Index
-	 * for matches.  The results set should be filled out with the
-	 * intersection of the IndexEntry for each word.  If any word does
-	 * not appear in the index, then the result set should be empty.
-	 *
-	 * @param  text  The text to search for.
-	 * @param  res   The results set to fill in with matching indexes.
-	 */
-	void search(const std::string &, struct set *);
-
 	/**
 	 * Converts the input text to lowercase and returns the result.
 	 *
@@ -50,4 +39,7 @@ void filter_deinit();
 /* Add the input string to the index. */
 void filter_add(const gchar *, unsigned int);
 
+/* Search for the input string in the index. */
+void filter_search(const gchar *, struct set *);
+
 #endif /* OCARINA_CORE_FILTER_H */
diff --git a/tests/core/filter.cpp b/tests/core/filter.cpp
index 60c7dd5c..505d78b1 100644
--- a/tests/core/filter.cpp
+++ b/tests/core/filter.cpp
@@ -34,35 +34,35 @@ static void test_filter()
 	} test_loop_passed();
 
 	/* Search for a word! */
-	filter :: search("hyrule", &res);
+	filter_search("hyrule", &res);
 	test_equal(set_size(&res), 3);
 	test_equal(set_has(&res, 1), (bool)true); /* hyrule symphony */
 	test_equal(set_has(&res, 3), (bool)true); /* hyrule field    */
 	test_equal(set_has(&res, 4), (bool)true); /* hyrule castle   */
 
 	/* A second search should clear the set. */
-	filter :: search("zelda", &res);
+	filter_search("zelda", &res);
 	test_equal(set_size(&res), 2);
 	test_equal(set_has(&res, 11), (bool)true); /* princess zelda             */
 	test_equal(set_has(&res, 13), (bool)true); /* the legend of zelda medley */
 
 	/* Partial word search. */
-	filter :: search("ko", &res);
+	filter_search("ko", &res);
 	test_equal(set_size(&res), 2);
 	test_equal(set_has(&res, 0), (bool)true); /* koji kondo    */
 	test_equal(set_has(&res, 2), (bool)true); /* kokiri forest */
 
 	/* Multiple word search. */
-	filter :: search("hyrule field", &res);
+	filter_search("hyrule field", &res);
 	test_equal(set_size(&res), 1);
 	test_equal(set_has(&res, 3), (bool)true); /* hyrule field    */
 
 	/* Search for unknown word. */
-	filter :: search("field termina", &res);
+	filter_search("field termina", &res);
 	test_equal(set_size(&res), 0);
 
 	/* Search for empty string. */
-	filter :: search("", &res);
+	filter_search("", &res);
 	test_equal(set_size(&res), 0);
 
 	filter_deinit();
diff --git a/tests/core/tags/track.cpp b/tests/core/tags/track.cpp
index a40dd3b2..d2cb6939 100644
--- a/tests/core/tags/track.cpp
+++ b/tests/core/tags/track.cpp
@@ -144,20 +144,22 @@ static void test_track_filter()
 {
 	struct set search = SET_INIT();
 
-	filter :: search("Title Theme", &search);
+	filter_search("Title Theme", &search);
 	test_equal(set_size(&search), (size_t)1);
 	test_equal(set_has(&search, 0), true);
 
-	filter :: search("Koji Kondo", &search);
+	filter_search("Koji Kondo", &search);
 	test_equal(set_size(&search), (size_t)1);
 	test_equal(set_has(&search, 0), true);
 
-	filter :: search("Hyrule Symphony", &search);
+	filter_search("Hyrule Symphony", &search);
 	test_equal(set_size(&search), (size_t)1);
 	test_equal(set_has(&search, 0), true);
 
-	filter :: search("No Track", &search);
+	filter_search("No Track", &search);
 	test_equal(set_size(&search), (size_t)0);
+
+	set_deinit(&search);
 }
 
 static void test_track_compare()