  We construct the regularized Wheeler--De Witt operator demanding that the
algebra of constraints of quantum gravity is anomaly free. We find that for
only a small subset of all wavefunctions being integrals of scalar densities
this condition can be satisfied. It turns out that the resulting operator is
much simpler than the one used in \cite{JK} to find exact solutions of
Wheeler--De Witt equation. We proceed to finding exact solutions of quantum
gravity and we discuss their interpretation making use of the quantum potential
approach to quantum theory.
