Add a Textbox.
Then setup the OnChange event in the Events-tab of the widget and switch apply changes to ‘while user is entering data’.
In this onchange, you can call a microflow with every filter you like.
Maybe do a ‘refresh in client’ in the microflow, so that the filtering is reflected on the screen.
However, to let this work you need a ViewObject.
This can be a nonpersistable object with a attribute ‘search’ (for the textbox) and with a relation to the article.