The England international was signed by former United manager Sir Alex Ferguson for £15m in January before being loaned back to Crystal Palace.
Moyes has been keen to keep Zaha at Old Trafford rather than send him out on loan again this season and he played in the Community Shield victory over Wigan at Wembley in August.
That is as near as the 20-year-old has come to the first team but Moyes insists he is still in his long-term plans.
"Wilf is one of the boys we have not been able to have a look at so far," he said.
"We always said we wanted him in. We needed him to see exactly what the level is like, and the boy is doing well.
"But Premier League games are important. We have to win them.
"So whilst there will be some players who get the opportunities sooner rather than later, some will have to wait their time because it is a fact you can only play 11."