Splicing tracks

Stupid question: When I zoom in very close on upper and lower tracks to splice them, I then export audio to WAV, but the only thing exported is what was shown on the window. But if I zoom out after splicing, I can’t see the beginning of the project. Is there a way to lock the two tracks once I get a good clean splice of a live performance so I can see the whole project in the window before I export it to audio? Thanks!

Ensure that you are using the current Audacity 2.2.2 version (available here: Audacity ® | Downloads)
A normal export will export all audio in the project except for muted tracks.
“Export Selected Audio” will export just the audio that is selected.