This paper addresses the problem of flexible procurement of multiple services with multiple non-functional characteristics, i.e., quality of service attributes. We consider the one-to-many negotiation approach as a flexible method for procuring multiple services by a buyer agent. We address the problem of coordinating multiple concurrent negotiations and propose a novel dynamic negotiation strategy that considers the behaviors of the opponents of the current negotiation encounter in managing the local reservation values of the common negotiation issues (attributes) of different services. Most previous works consider the problem of negotiation over a single issue. We investigate a more complex situation where a buyer agent negotiates over multiple services given that each service has multiple negotiation issues. The experimental results show an evidence for the effectiveness and robustness of our dynamic negotiation strategy in various negotiation environments.