XAML itself
<ComboBox x:Name="comboBox" Grid.Column="1" HorizontalAlignment="Left" VerticalAlignment="Center" Width="350" Height="auto" IsEditable="True" PreviewTextInput="comboBox_PreviewTextInput" ToolTip="Введите первые 3 буквы фамилии" Padding="5,5,5,5" SelectionChanged="comboBox_SelectionChaned" > <ComboBox.ItemTemplate> <DataTemplate> <TextBlock> <TextBlock.Text> <MultiBinding StringFormat="{}{0} {1} {2} {3} {4:dd.MM.yyyy}"> <Binding Path="id"/> <Binding Path="fam"/> <Binding Path="name"/> <Binding Path="parent"/> <Binding Path="DOB"/> </MultiBinding> </TextBlock.Text> </TextBlock> </DataTemplate> </ComboBox.ItemTemplate> </ComboBox> This is how the combobox list is filled.
var result = db.Athletes .AsEnumerable() .Where(c => c.fam.ToLower().StartsWith(comboBox.Text.ToString())) .Select(c => new { c.id, c.fam, c.name, c.parent, c.DOB } ) .Take(20) .ToList() ; comboBox.IsDropDownOpen = true; comboBox.ItemsSource = result; 

Template. Show more code (and yourDataContext) - VladD