Trivago NV, the German hotel search site that went public in December, isn’t concerned about competitive threats from rivals TripAdvisor Inc. and Priceline Group Inc., as the market is still big enough for everyone to grow. Sales are expected to increase 45 percent to around 1.1 billion euros in 2017, the Dusseldorf, Germany-based company said Friday, sending shares up as much as 4.8 percent in New York.