Willy Boly headed home for the hosts, but his effort was chalked off after the technology intervened – Pedro Neto marginally offside in the build-up.
And Nuno, whose side have also had goals not count in the reverse fixture against the Foxes and at both Liverpool and Manchester United this term, said: "The law is the law, but the question is whether it is a clear advantage.
"I'm upset, of course, as Molineux was buzzing and suddenly it went down.
"It becomes an issue to regain concentration in the game. It's very hard for the players to sustain the levels of concentration after this kind of decision.
"And after seeing the images, it's even worse for the fans – all these things.
"Let's hope those who have to decide take a good look, see what is happening.
"Not only for us as professionals, but for the fans. Something has to be done."
Boly, set up by Matt Doherty's header across the face of goal, was forced into a long wait before finding out his goal did not stand.
And Nuno said on the confusion: "They don't understand as they don't see, they don't have the lines.
"They celebrate. When you have something and someone takes it away, you don't like it.
"Something that is really hard to achieve is a goal, but the law is the law."
On whether Wolves are getting an unfair share of the decisions, Nuno said: "It can be on both sides but, unfortunately, it has happened more times for us and that upsets us.
"But it's not about Wolves, it's about the game. It's about what we have and where we want to go, what kind of game we want to see and how the fans will react. It's all of these things."
With Wolves now seventh in the Premier League, Nuno added on the performance: "We did a very good game, a very good performance.
"We created a lot of chances in the second half and totally dominated. This is what we did."