VirtualDub: how to select multiple segments for encoding

Hi, I would like to know how to select multiple segments of a video for encoding in VDub. I don't know if VDub is capable of doing this but FlaskMPEG can do it, where you can select a portion of beginning video and ending video and encode in one process.

I believe VDub uses the term offset. When I try to make a 2nd segment, the 1st is overwriten and gone.