My shih tzu keeps throwing up
i own a female shih tzu and she has been throwing up a lot lately. 3 times in the past 24 hours. we feed her a small bowl of dry dog food every day. I think it might be because of the 105 degree heat but she is only outside for maybe 2 hours a day total. she doesnt even make a big deal about it. she does it silently and then acts like nothing happens. while cleaning it up i have found some grass. is there something wrong with her? what can i do to stop this?