  We apply the nonlocal condensate formalism to construct generalized sum rules
(including $O(\as)$-radiative corrections) for $\pi$-, $\rho$- and
$\rho'$-meson wave functions of twist 2. Besides, we predict the lepton decay
constant $f_{\rho'}$ and estimate the mass of $\rho'$-meson. For all these
mesons we obtain the first 10 moments of longitudinal wave functions, suggest
the models for them and discuss their properties. We consider the peculiarities
of the QCD sum rules with nonlocal condensates for transverse $\rho$- and
$b_1$-meson wave functions. These results are compared with those found by Ball
and Braun and by Chernyak and Zhitnitsky.
