diff --git a/src/main/java/io/github/ashwith/flutter/FlutterFinder.java b/src/main/java/io/github/ashwith/flutter/FlutterFinder.java
index e3b66fa..5bf4d54 100644
--- a/src/main/java/io/github/ashwith/flutter/FlutterFinder.java
+++ b/src/main/java/io/github/ashwith/flutter/FlutterFinder.java
@@ -85,8 +85,8 @@ public FlutterElement byText(String input) {
     public FlutterElement byAncestor(FlutterElement of, FlutterElement matching, boolean matchRoot, boolean firstMatchOnly) {
         Map<String, Object> matchIdentifier = new HashMap<>(ImmutableMap.of(
                 FINDER_TYPE, "Ancestor",
-                "matchRoot", matchRoot,
-                "firstMatchOnly", firstMatchOnly
+                "matchRoot", Boolean.toString(matchRoot),
+                "firstMatchOnly", Boolean.toString(firstMatchOnly)
         ));
         matchIdentifier.put("of", of.getRawMap());
         matchIdentifier.put("matching", matching.getRawMap());
@@ -100,8 +100,8 @@ public FlutterElement byAncestor(FlutterElement of, FlutterElement matching, boo
     public FlutterElement byDescendant(FlutterElement of, FlutterElement matching, boolean matchRoot, boolean firstMatchOnly) {
         Map<String, Object> matchIdentifier = new HashMap<>(ImmutableMap.of(
                 FINDER_TYPE, "Descendant",
-                "matchRoot", matchRoot,
-                "firstMatchOnly", firstMatchOnly
+                "matchRoot", Boolean.toString(matchRoot),
+                "firstMatchOnly", Boolean.toString(firstMatchOnly)
         ));
         matchIdentifier.put("of", of.getRawMap());
         matchIdentifier.put("matching", matching.getRawMap());
@@ -139,4 +139,4 @@ public FlutterElement bySemanticsLabel(Pattern label) {
     public FlutterElement pageBack() {
         return new FlutterElement(ImmutableMap.of(FINDER_TYPE, "PageBack"));
     }
-}
\ No newline at end of file
+}