Now I have to find a gap in Literature. My supervisor told me to look into rehab

Now I have to find a gap in Literature. My supervisor told me to look into rehabilitation and transitions, as well as the unmet needs of stroke patients. This should include Saudi Arabia, but it should also identify international and national guidelines for stroke care – that’s also, the components of good quality stroke care and how they can be delivered and assessed. I’m not sure if my supervisors want me to read around my topic or focus on this area, but you are very expert in guiding me to start my systematic literature review. I need your assistance with search strategy and keywords, as well as how many studies I have to move forward with an included title for each of them”