puckering drywall question

I am repainting my bathroom, and had to remove some wallpaper. When they installed the wallpaper, they didn't prime the drywall first, so it was really hard to remove. When I was patching some of the holes/scratches (using joint compound - not spackle), some parts of the drywall paper started to pucker up and leave little bubbles under the paper of the drywall. How can I fix this without replacing the drywall?
Thank you

 

Use a utility knife to cut out the loose spots of paper, then use drywall tape and joint compound to make a new surface. Also, I prefer paper tape over the self-stick mesh, and be sure to put joint compound underneath the paper.