A higher oscillation frequency is associated with greater acceleration, and greater acceleration gives stronger re-radiation. So since the incoming wave has the same frequency as the oscillation, the higher the frequency of the incoming wave the stronger the re-radiation. So this explains why blue light scatters more strongly than red .It’s because the strength of scattering of light depends on the frequency (or wavelength) of the light wave as well as the properties of the scattering particle.