WPF - Select ComboBox value by typing when using DataTemplate

Question

I have a combobox in wpf which is binded to some property (another object). Because I need to show two properties of that object i used DataTemplate inside combobox. Now when combobox is in focus I can't select some value by typing few starting letters (without DataTemplate it is possible).

<ComboBox Height="23" HorizontalAlignment="Left" Margin="104,14,0,0" Name="tipDokumentaCombo" VerticalAlignment="Top" Width="241" TabIndex="0" ItemsSource="{Binding Path=TipoviDokumenta}" SelectedValue="{Binding Path=Potvrda.Tip}" SelectedValuePath="Tip" SelectionChanged="tipDokumentaCombo_SelectionChanged">
            <ComboBox.ItemTemplate>
                <DataTemplate>
                    <StackPanel Orientation="Horizontal">
                        <TextBlock Text="{Binding Path=Tip}" />
                        <TextBlock Text=" (" />
                        <TextBlock Text="{Binding Path=OpisDokumenta}" />
                        <TextBlock Text=")" />
                    </StackPanel>
                </DataTemplate>
            </ComboBox.ItemTemplate>
        </ComboBox>

Answer 1

Set TextSearch.TextPath to the property that should be searched.

Update
Because the abvove solution seems not to work for you, try to set the search text manually for the container:

<ComboBox.ItemContainerStyle>    
   <Style TargetType="{x:Type ComboBoxItem}">        
          <Setter Property="TextSearch.Text" Value="{Binding Tip}" />            
    </Style>
</ComboBox.ItemContainerStyle>