  We study the inclusion of new heavy fermions on complex scalar dark matter
(DM) phenomenology within gauged two Higgs doublet model (G2HDM). We find that
for DM mass above 1 TeV, heavy quarks coannihilations into the Standard Model
(SM) quarks and gluons dominate the thermally-averaged cross section relevant
for the relic abundance of complex scalar DM. We demonstrate that the effects
of QCD Sommerfeld correction as well as QCD bound state formation in
determining the DM relic are negligible. We show that the allowed parameter
space is significantly constrained by the current PLANCK relic density data as
well as XENON1T limit appropriate for DM direct search.
