How can I get my 14th month old to talk more?

He always says "dada" repeatedly..He has said other things in the past when he was younger,but only a few times.He says mama on occasion, but usually its only dada or nye nye(night night).Is this normal for his age?I am worried he isn't talking as much as he should be.I read to him sometimes and talk to him a lot.Is there anything else I can do?