What Makes A Dog Vomit?

Anyone know? Abby threw up yesterday and today. Granted, she does eat things other than dog food....I haven't swept the kitchen floor in weeks. She finds a jackpot under Liam's chair after every meal. Then there is the straw broom that was left out on the deck that she totally tore apart. Also, she eats really fast. She doesn't even chew her food. Could any of these things be the cause? Maybe I'll do a Google and see what I can find.
Read on if you stomach is strong enough because I'm going to tell you something really disgusting........She eats her puke. Is this normal? Do all dogs do this? Do we need to take her to the vet?

PS...I did a search and found this very informative article, in case anyone else is wondering.
http://aboutdoghealth.blogspot.com/2007/09/dog-vomiting.html


KKS