if there is higgs boson, is it possible that there is higgs quarks which might be hiding in natural isotops?

No, that's not how things work. Quarks are the building blocks of hadronic matter (e.g. neutrons, protons). Bosons are force carrier particles (e.g. electromagnetic, strong nuclear, and weak nuclear forces). Quarks and bosons have nothing to do with each other, other than one (bosons) carries forces for the other (quarks).