In this contribution, two simplified MVD derivation methods for MMVD are introduced by restricting the usage of the POC difference. In method 1, using the POC difference is restricted when a current block refers any long-term reference picture. In method 2, using the POC difference is always restricted. For method 1, the experimental results reportedly show no changes in coding performance and run-time compared to VTM5.0 as anchor in CTC. For method 2, the experimental results reportedly show 0.xx% BD-rate changes with xx% and xx% encoding and decoding run-time compared to VTM5.0 as anchor in RA configurations.