  We derive a general effective many-body theory for bosonic polar molecules in
strong interaction regime, which cannot be correctly described by previous
theories within the first Born approximation. The effective Hamiltonian has
additional interaction terms, which surprisingly reduces the anisotropic
features of dipolar interaction near the shape resonance regime. In the 2D
system with dipole moment perpendicular to the plane, we find that the phonon
dispersion scales as $\sqrt{|\bfp|}$ in the low momentum ($\bfp$) limit,
showing the same low energy properties as a 2D charged Bose gas with Coulomb
($1/r$) interactions.
