Generally the most effective way to search for a topic is by using databases, however, sometimes you may want to look at a specific journal. Following is a list of some of the top rated journals in Social Work, according to the 2012 JCR, Journal Citation Reports. These are ranked by "impact factor," a measure of their influence in the discipline. While the JCR rankings may be somewhat controversial, they are nonetheless, a well-known standard in academia.
There are many,many more Social Work journals available from the MU Libraries. Use databases to identify articles from journals on a specific topic, or if you have a journal title in mind, click on Journal Finder from the libraries' home page.