This blog defines multi trigger in WPF.

<Window x:Class="TypesOfTriggersDemo.MultiTRiggerDEmo"

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

Title="MultiTRiggerDEmo" Height="300" Width="300" Loaded="Window_Loaded">

<Window.Resources>

<Style x:Key="MultTrigg" TargetType="{x:Type TextBox}" >

<Style.Triggers>

<MultiTrigger>

<MultiTrigger.Conditions>

<Condition Property="IsFocused" Value="True"></Condition>

<Condition Property="IsMouseOver" Value="True"></Condition>

</MultiTrigger.Conditions>

<MultiTrigger.Setters>

<Setter Property="Background" Value="yellow" ></Setter>

</MultiTrigger.Setters>

</MultiTrigger>

</Style.Triggers>

</Style>

</Window.Resources>

<StackPanel>

<TextBox Style="{StaticResource MultTrigg}"></TextBox>

</StackPanel>

</Window>