In order to improve the adaptability and efficiency of federating method for disjoint segments in wireless sensor network (WSN) under the unknown distribution of disjoint segments and bandwidth-constrained relay, an optimization problem about multi-robot federating for disjoint segments in WSN based on search and bandwidth aware (MRF-SNSA) is proposed, and approximate solution algorithms for the optimization problem are given. Firstly, according to the related model assumptions and symbol definitions, the iterative process of synchronizing the step-flow rounding is introduced referring to the idea of the iterated local search and flow shop scheduling, and the formal definition for MRF-SNSA is established. After that, based on the overlapping-aware connectivity search algorithm, a hierarchical relay deployment algorithm with the search and bandwidth aware is designed using related theories of hierarchical clustering and network flow. Finally, through experiments and comparison with the existing method, the experimental results show that the proposed method can effectively improve the efficiency of federating disjoint segments in WSN while meeting the constraints for the unknown distribution of disjoint segments and the bandwidth-constrained relay.