Traditional IP-based unicast routing cannot utilize the inherent broadcast property of wireless network, and unicast path can be broken down frequently due to node mobility. Based on the nature of named data networking (NDN) which faces “content” rather than “host”, broadcast mode can be applied for content delivery in named data mobile ad hoc networks (ND-MANETs). However, since there are no acknowledgment and retransmission mechanisms in the broadcast mode of IEEE 802.11 protocol, it would cause the problem of transmission unreliability. Moreover, if all forwarding nodes transmit packet concurrently, it can easily lead to collision and redundancy. This paper presents a reliable broadcasting-based content acquisition scheme for highly dynamic ND-MANETs, which makes full use of the inherent broadcast nature of wireless network, and solves the unreliability, collision, and redundancy problems. We define Transmission Reliability Degree ($TRD$) for broadcast mode, and estimate its value through Markov model. A content-oriented and $TRD$ of sending node-based resend algorithm is proposed to improve reliability of broadcast transmission. An area divided and $TRD$ of receiving node-based reforwarding algorithm is proposed to reduce collision and redundancy. Simulation results demonstrate the effectiveness and efficiency of the proposed mechanism.