Your hypotheses and research questions depend on how much you want to investigate in your thesis statement. I wonder why you should worry about their number if they are reasonably few, e.g. 4 to 5. If you have more than that, nobody can help if they don't know what you want to research.
Usually, 3 to 4 hypotheses are enough in a study at PhD level. But it depends on your research and your supervisor or guide may help you to formulate sufficient number of hypotheses.
Hypotheses are often linked to the independent variables being studied. This is a tricky thing; you have to keep from ignoring the important ones and you have to assess unimportant ones. The lesser important ones are usually minor demographic variables or minor variables within a marketing mix approach.
You cannot leave out an important independent variable. For example, in testing if people like to see cowboy movies, age is an important variable. But gender may be equally important.
Non-academically speaking, write out everything you want to know, meaning make a list of all your hypotheses and then see if you can combine any of them, if there's any redundancies, or anything that is extraneous beyond your research.