Mobile ad-hoc networks (MANETs) are temporary networks without any pre-existing infrastructure in which nodes are connected through wireless channels. There is no centralized administration in this network because nodes are not fixed at their locations, they are continuously moving to different locations. Each node in MANETs has dynamic capabilities because at one point acts as a host while in some other time becomes a router which can forward messages on the network to other nodes. One of the complicated issues in MANETs is routing due to their dynamic topology which is frequently changes due to the mobility of nodes. In order to forward packets in this complex topology using optimal routes, there is a need for efficient routing protocols. There are three categories of routing protocols in MANETs named as reactive, proactive and hybrid respectively. We have used a hybrid type protocol named Zone Routing Protocol (ZRP) for routing in our research. In order to control unwanted flooding in the overlapping zones of ZRP, we have proposed a selective broadcasting technique for route discovery. In this technique route discovery exchange messages are highly reduced in the outer zone of the ZRP.