<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <android.support.v7.widget.CardView xmlns:card_view="http://schemas.android.com/apk/res-auto"
        android:id="@+id/card_view"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_gravity="center"
        android:layout_marginBottom="6dp"
        android:layout_marginEnd="10dp"
        android:layout_marginStart="10dp"
        android:layout_marginTop="6dp"
        card_view:cardCornerRadius="4dp">

        <TextView
            android:id="@+id/content"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:padding="5dp"
            android:textSize="16sp" />
    </android.support.v7.widget.CardView>
</LinearLayout>
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <android.support.v7.widget.CardView xmlns:card_view="http://schemas.android.com/apk/res-auto"
        android:id="@+id/card_view"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_gravity="center"
        android:layout_marginBottom="6dp"
        android:layout_marginEnd="10dp"
        android:layout_marginStart="10dp"
        android:layout_marginTop="6dp"
        card_view:cardCornerRadius="4dp"
        card_view:cardElevation="10dp">

        <TextView
            android:id="@+id/content"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:padding="5dp"
            android:textSize="16sp" />
    </android.support.v7.widget.CardView>
</LinearLayout>
Add card elevation to 10dp
ptch: Add card elevation to 10dp
