tachiyomi/app/src/main/res/menu/library.xml

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools" tools:context=".MainActivity">
    <item
        android:id="@+id/action_search"
        android:title="@string/action_search"
        android:icon="@drawable/ic_action_search"
        android:orderInCategory="100"
        app:showAsAction="collapseActionView|ifRoom"
        app:actionViewClass="android.support.v7.widget.SearchView"/>
    <item
        android:id="@+id/action_refresh"
        android:title="@string/action_refresh"
        android:icon="@drawable/ic_action_refresh"
        android:orderInCategory="1"
        app:showAsAction="ifRoom" />
</menu>