Cooperative search is one of the important parts for multi-UAVs cooperative tasks. Path planning is the way to achieve multi-UAVs cooperative search problem. In this paper, the development history of cooperative search problem is investigated firstly. Then, the application scope of several typical environment model construction methods is compared. Finally, the traditional and new path planning algorithms are analyzed. With the rapid development of science and technology, the cooperative search strategy models become more complex. All these bring challenges to the design of top-level architecture and intelligent algorithm. The key to the development of multi-UAVs cooperative search is to further improve the degree of intelligence.