Finding Dissertations
Use a subject-specific database (ERIC, PsychInfo) to search for theses and dissertations related to your to research. Look for the field or option to refine your search to just dissertations.

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Many dissertations are now digitized, so try entering the title in Google to see if the manuscript is online.  If not, you can request the item through interlibrary loan although not all institutions will lend their theses or dissertations.

Another option is to us PQDT Open. PQDT Open provides the full text of open access dissertations and theses free of charge.