  Using the factorization approach and taking into account the final state
interaction, we calculate the two body non-leptonic decays of doubly heavy
baryons. After comparing the semi-leptonic decays and all possible hadronic
decay channels, we found some channels with large branching ratios. Taking the
detection efficiency into consideration, we suggest $\Xi_{cc}^{++}$ as the
first search goal and $\Xi_{cc}^{++}\to \Lambda_c^+K^-\pi^+\pi^+$ and
$\Xi_{cc}^{++}\to\Xi_{c}^{+}\pi^{+}$ as the golden discovery channels with
$\Lambda_c^+$ reconstructed by $pK^-\pi^+$ and $\Xi_{c}^+ \to p K^- \pi^+$,
respectively.
