In the Philippines, an academic thesis is named by the degree, such as bachelor/undergraduate thesis or masteral thesis. However, in Philippine English , the term doctorate is typically replaced with doctoral (as in the case of "doctoral dissertation"), though in official documentation the former is still used. The terms thesis and dissertation are commonly used interchangeably in everyday language yet it generally understood that a thesis refers to bachelor/undergraduate and master academic work while a dissertation is named for doctorate work.
Again, the methodology of your work should be in strong accordance with the initial thesis and the main aim of your research. Visit the university library - the librarians might be eager to provide you with a good textbook as well as with a recommendation on how to start a cover letter . Thus, a lot of books can teach you research philosophy, so that you will be able to choose methods on your own. Moreover, it is convenient to look for someone else's thesis methodology example in the library. Remember, only deep theoretical knowledge can help you to reinforce your dissertation with firm methodological underpinnings.