Do I have enough time by fast train from Xian to Luoyang for a round trip on a same day?

I'm afraid time is a little tight for a round trip between the two places in a day. Shaolin Temple, Longmen Grottoes and White Horse Temple are very attractive spots there. You can fully enjoy yourselves there, and go back to Xian in the next morning. Near the railway station, there are tourist buses to the temple directly.