  The improved calculation method of quark distributions in hadrons in the
framework of QCD sum rules is presented. The imaginary part of the virtual
photon scattering amplitude on some hadronic current is considered in the case,
when initial and final virtualities of the current $p^2_1$ and $p^2_2$ are
different, $p^2_1\not= p^2_2$. The double Borel transformation in $p^2_1,
p^2_2$ is applied to the sum rule, killing background non-diagonal transition
terms, which deteriorated the accuracy in the previous calculations. Valence
quark distributions in the pion were found in a good agreement with the data,
determined from the Drell-Yan process.
