In this paper, the usefulness of nonlinear processes in complex dynamic systems for efficiency enhancement of measuring devices based on such systems is substantiated. The analysis of sensitivity and selectivity of resonance measurement techniques including ones based on coupled oscillations in piezoresonance structures is provided. It is demonstrated that there are certain specific oscillation frequencies with high sensitivity to changes in several parameters of sensor oscillation system and low sensitivity to changes in other parameters simultaneously. Thus, it is concluded that optimizing design and operational modes of measuring device would provide the possibility to enhance sensitivity and selectivity of a measurement process. It is shown that one-degree-of freedom systems are capable of producing highly efficient capacity measurement of a capacitor when the sensor output is the voltage on inductance; and inductance measurement when sensor output is the capacitor voltage in the equivalent circuit of the sensor. Two-degree-of-freedom systems demonstrate high efficiency and sensitivity for frequencies that correspond to normal synchronization frequencies of the systems.