Nesting More Than One Drawing

I have searched the forum and tried everything to no avail. How do I nest more than one drawing? Every time I get my first drawing nested and then try to import the second drawing, the first one disappears. I know it is something simple but cant figure it out. Thank you.

A part can only have one drawing. If you load another drawing into that part it replaces the previous one. Go to File->new part. You can then load your drawing into that part. Repeat for as many parts as you want.