You can export just a specific part of your drawing by exporting your Selection.
- Ensure your app is updated to the most recent version.
 - Select the strokes or objects you wish to export.
 - Tap the Export icon in the status bar.
 - In the Export menu, choose your file type and other settings. Under the Region section, the option will be automatically set to Selection.
 - Tap Export and save the file to your desired location.