Smart objects (SOs) have been utilized widely to transform the physical environment around us to a digital world using the Internet of things (IoT) vision. Integrating a huge number of these devices into the Internet presents a significant necessity for an efficient discovery mechanism with high capability of an autonomous configuration and detection for theses devices and their provided services. Instead of developing new protocols to provide such functionalities, community resorted to adapting already existing protocols such as multicast Domain Name System (DNS) and DNS-Service Discovery (DNS-SD) as they are the most extended discovery protocols for Internet architecture nowadays. Since these protocols have been designed mainly for the ordinary computational devices without considering of the low capability constraints of SOs, it is not applicable to apply them directly on the SOs. To this end, this work proposes an optimization approaches to minimize the overhead caused by some operations of mDNS/DNS-SD protocols. Probing and advertisement suppression (PAS), discovery responses suppression (DRS) approaches and selection stage optimization (SSO), namely, are proposed and explained in this paper.