I am trying to create a custom lookup search in lwc and after selecting the record from the lookup I have to click an add button so that it would be added to a lwc datatable. But my problem is when I am clicking the add button only the data from current searc is coming to the table removing the previously added data.

I am trying to create a custom lookup search in lwc and after selecting the record from the lookup I have to click an add button so that it would be added to a lwc datatable. But my problem is when I am clicking the add button only the data from current searc is coming to the table removing the previously added data.