My dog eats evrything except its food esp. cowdung puts her mouth on evry thng she finds pls hlp me to stop it

her age is 7 months now. she doesn eat d food kept in her bowl but she try to eat evry thing she finds on road wen i take her for walk. n also she doesn drink water poured in her bowl but drink water on road for sure.... pls help me to come out of this problem... i don want to beat or slap her....