In searching for materials on philosophy and mental health you may find it helpful to:
Working back and forth between the two kinds of resource (generic and targeted) can be productive.
A search strategy that combines generic and targeted resources is described through a clinical case example in;
Chapter 6, A Smoking Enigma: Getting (and Not Getting) the Knowledge, in Fulford, Peile and Carroll’s (2012) Essential Values-based Practice. Although concerned with retrieval of research on values the approach is generalisable to other topic areas
Many helpful academic resources can be found simply by using key terms to search on any of the large databases, such as Google or (if you want to restrict your results to journal papers, Google Scholar
Elsevier’s Scopus database is also very comprehensive
More specific subject-based indexes (many of which are accessible only via institutional libraries) include
Many of those working in philosophy and mental health have copies of their papers available on Academia.edu or ResearchGate.net as well their own university faculty web-pages (the latter are generally included in the indexes on other pages of the website as listed below).
University Faculty web-page entries are included in the indexes on other pages of the INPP website as listed in 2. Searching the INPP Website).
Academic (and many public) libraries will generally offer help in accessing materials on a given topic.