You absolutely can - just go into Management > Saved objects.
Select the saved objects (dashboards and visualizations) you need, and press the export button.
This will download the configuration as an ndjson file to your local computer and you can later upload it again into another Kibana instance using the import button on the same page.
Reference: https://www.elastic.co/guide/en/kibana/current/managing-saved-objects.html