As someone with few resources, I can only do market research through observations, talking to people and using google questionnaires in addition to finding secondary research done on the topic. However, is this method of "market research" acceptable when I want to present my ideas to potential investors? Is there some sort of more valid form of market research?
I think if you really want to win the "YES" of your potential investors when you present your ideas,you should have a profound and realistic ideas that pertains to your subject.
Google is way enough but make sure to search the exact wordings that pertains to your project so it will give you specific inputs.
Speaking of inputs, why not try to make a consultation to the expert. They have the best ideas how you can make your presentation a success.