When providing information services for users in libraries, it is essentially important to understand how they make use of multiple information resources and included information. There have been many studies about users' preference, information seeking behavior, and learning effects in individual resources. However, there is little empirical research about how users search for information and what problems exist in such information seeking processes in the environment including multiple information resources. In this study, we try to understand how participants search for their needed information in a university library consisted of physical and electronic information resources. In our experiments, we revealed the participants' general use of information resources and the effect of definiteness of their goal state manipulated experimentally. The results of our study are summarized as follows. First, their use of information resources was biased toward either physical resources or electronic resources. Second, they often switched information resources without definite reason about what they wanted to found out on there. Third, even if they had a precise intention about what they searched for, they encountered and picked up unintended information during their search process. And finally, the clear goal state experimentally operated affected use of multiple information resources and generation of information needs.