Overide couple images over toolbar foreground image

Question

I have next layout:

UPDATED CODE

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/res-auto"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/relativeLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/window_background_color"
android:clickable="false">

<!-- Toolbar  -->
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/toolbar"
    android:layout_width="0dp"
    android:layout_height="60dp"
    android:elevation="1dp"
    android:foreground="@drawable/titlebar_1"
    android:foregroundGravity="center|fill"
    android:minHeight="?attr/actionBarSize"
    android:titleTextAppearance="@color/white"
    app:layout_constraintBottom_toTopOf="@+id/test"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent"
    app:popupTheme="@style/Theme.AppCompat">
</android.support.v7.widget.Toolbar>

<!-- tips&tricks  -->

<ImageView
    android:id="@+id/imageView3"
    android:layout_width="247dp"
    android:layout_height="wrap_content"
    android:layout_marginBottom="8dp"
    android:layout_marginEnd="8dp"
    android:layout_marginStart="8dp"
    ads:layout_constraintBottom_toTopOf="@+id/test"
    ads:layout_constraintEnd_toEndOf="parent"
    ads:layout_constraintStart_toStartOf="@+id/toolbar"
    ads:srcCompat="@drawable/common_google_signin_btn_text_dark_focused" />

<RelativeLayout
    android:id="@+id/test"
    android:layout_width="0dp"
    android:layout_height="33dp"
    android:background="#1c3049"
    android:orientation="horizontal"
    ads:layout_constraintBottom_toTopOf="@+id/map"
    ads:layout_constraintEnd_toEndOf="parent"
    ads:layout_constraintHorizontal_bias="0.0"
    ads:layout_constraintStart_toStartOf="parent"
    ads:layout_constraintTop_toBottomOf="@+id/toolbar">

</RelativeLayout>

</android.support.constraint.ConstraintLayout>

I need to display 3 images over toolbar foreground image. But all my tries have fail.

I need to add three transparent buttons image over red area. Actual ImageView is hide by toolbar image. How can I put it on top of toolbar ? Any advice for me?