For the two-body anti-triplet charmed baryon decays, there exist two theoretical analyses based on the SU (3) flavor (SU (3) f ) symmetry. One is the irreducible SU (3) f approach (IRA), which depends on the irreducible SU (3) f representation of the effective Hamiltonian. The other is the topological-diagram approach (TDA), where the decays are drawn to consist of W -boson emission and W -boson exchange topologies. We demonstrate that IRA and TDA can be equivalent, such that the IRA parameters can be seen to mix with the TDA topologies. The current observationsIt is found that a specific W -boson exchange topologydenoted by E M only appears in Ξ 0 c → BM , by which we explain B(Ξ 0 c → Λ 0 K0 ). In addition, we predict B(Ξ 0 c → Σ 0 K0 , Σ + K − ) = (5.8 +4.7 −3.5 , 5.4 +4.9 −3.4 ) × 10 −3 for future measurements to test if E M can be a significant contribution.