If you've added Tags to your client profiles, it's super easy to search using the Tags. See the GIF below to see how it's done.
Once you've found your clients using your tags, you can then easily export their information to whatever email messaging app you use. Watch the GIF below to see how it's done.
As you can see from the GIF, you simply click the boxes next to the profiles you'd like to export then click the button in the top right corner of the screen that says Export XLS when hovered over. From there, you'll check the fields you'd like to be exported (ex. First Name, Last Name, Email) and then Export. An XLS file will be downloaded for you and you will then use that in your messenger app.