  We consider the shape of the curves of "Andreev" conductance of non-ballistic
point contact NS heterosystems depending on the bias voltage at the contact.
The obtained shape of those curves is caused by the contribution from the
mechanism of coherent scattering by impurities which doubles the scattering
cross section. The behavior of generalized and differential conductance is
compared for ballistic and non-ballistic transport regimes. The criteria are
considered allowing one to discriminate between those regimes with the
corresponding conduction curves similar in appearance. The analysis is extended
to the case of non-ballistic transport in NS point contacts with exotic
superconductors, molybdenum carbide Mo-C and oxypnictide
La[O$_{1-x}$F$_{x}$]FeAs from a group of iron-based superconductors.
