An exact proof term for the current goal is CD_minus_mul_distrL {2} SNo complex_tag_fresh minus_SNo conj add_SNo mul_SNo SNo_minus_SNo (λx H ⇒ H) SNo_add_SNo SNo_mul_SNo minus_add_SNo_distr mul_SNo_minus_distrR mul_SNo_minus_distrL.