This document discloses a solution for carrying out narrowband communications in a wireless network. According to an aspect, a method comprises in an apparatus: detecting at least one content notification message indicating contents of each of a plurality of messages frequency-multiplexed with a discovery message to parallel sub-channels of a channel in a bi-directional wireless network; selecting autonomously a sub-channel on the basis of the detected content notification message; and acquiring a message through the selected sub-channel.