Since we have several ways of speaking depending on the person, the relationship between people, the form of informal and formal, the gender, etc, there are various translations. JucCc's answers are some of them. The basic and general ones are: もうすこしたべたいです。 もっとたべたいです。 *We say "want to eat" in literal translation. I hope this helps you.

I think you can use one of them.... These means.... I still want to eat.. まだ食べたいよ。 まだまだ食べ欲しい。 I hope I helped you :)