Subject search terms to use in SOLO include the following
Law -- Social aspects
Law and anthropology
Effectiveness and validity of law
Law -- Psychological aspects
You don't need to do a special type of search for the results to include ebooks - but you could apply a filter before or after searching to either Online Resources or Physical Resources by using the drop down menu in the search box.
Take note of the location of any books in print, you may well find interesting works in other parts of the Bodleian not only Law Bod and/or the Social Science Library - but others too.
If you are having difficulties using SOLO the online guide below should be able to help:
Examples of titles in the Law Bod are