How to define user’s problem in Clean Eating

Hello everyone, I’m Mai. I’m a totally fresher in UX and recently I’m working on a mentoring project (Product Design) where I need to find a solution to make Clean Eating Journey become easier. But I’m so trouble in finding their true pain points (like the one that most deserves to be solved). I’ve conducted a survey, interview and even diary study but their answer are so general, I couldn’t come to any conclusion. I guess maybe my Interview technique has gone wrong.
Do you have any ideas/solutions that might help me? I’m so stuck on this, thank you very much!

Thank you very much! I will read the book and keep rework my interview and survey.

Hello Mai. I think you should try to improve the questionnaire and question technique in research. Set up some assumptions (your vision), make some questions around the assumptions and figure it out. Try to use open-question instead of “yes/no question”. Good luck!