Characterizing the properties of matter at a single-molecule level is highly significant in today’s science, such as biology, chemistry, and materials science. The advent of generalized nanoscale sensors promises to achieve a long-term goal of material science, which is the analysis of single-molecule structures in ambient environments. In recent years, the nitrogen-vacancy (NV) color centers in diamond as solid-state spins have gradually developed as nanoscale sensors with both high spatial resolution and high detection sensitivity. Owing to the nondestructive and non-invasive properties, the NV color centers have excellent performance in single-molecule measurements. So far, the NV centers have achieved high sensitivity in the detection of many physical quantities such as magnetic field, electric field, and temperature, showing their potential applications in versatile quantum sensors. The combination with the cross measurements from multiple perspectives is conducible to deepening the knowledge and understanding the new substances, materials, and phenomena. Starting from the microstructure of NV sensors, several detections under the special magnetic field condition of zero field, including zero-field paramagnetic resonance detection and electric field detection, are introduced in this work.