To improve the coverage of multi-UAVs cooperative search, various communication constraints have to be considered: communication distance, communication delay and communication network structure. A kind of network building method based on tree concept of data structure is presented, and a communication strategy based on information fusion is proposed. These method and strategy could effectively improve the efficiency of multi-UAVs cooperative search. Different situations are designed to verify the rationality and validity of the proposed network building method and communication strategy for improving coverage rate of multi-UAVs cooperative search.