Hi,
i suggest you to check reader.xml of PDFReader layout folder.
These are the components used in the demo project to create the search box
<LinearLayout
android:id="@+id/bar_find"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentTop="false"
android:layout_centerInParent="false" >
<EditText
android:id="@+id/txt_find"
android:layout_width="150dp"
android:layout_height="40dp"
android:ems="10"
android:text="the" />
<Button
android:id="@+id/btn_prev"
style="?android:attr/buttonStyleSmall"
android:layout_width="40dp"
android:layout_height="wrap_content"
android:text="<" />
<Button
android:id="@+id/btn_next"
style="?android:attr/buttonStyleSmall"
android:layout_width="40dp"
android:layout_height="wrap_content"
android:text=">" />
</LinearLayout>