  We propose in this work a practical approach, by virtue of correlation
matrices of the generic observables, to study the long lasting tough issue of
quantum separability. Some general separability conditions are set up through
constructing a measurement-induced Bloch space. In essence, these conditions
are established due to the self constraint in the space of quantum states. The
new approach can not only reproduce many of the prevailing entanglement
criteria, but also lead to even stronger results and manifest superiority for
some bound entangled states. Moreover, as a by product, the new criteria are
found directly transformable to the entanglement witness operators.
