Here you can filter the data by Course (1), Student set (2), Date (3) where default range is last 30 days, Attempts (4), Sorting by name/forename/student set (5).
If a cell coloured green you can click on it to see the quiz results for this student, yellow one indicates quiz which has not been started yet. Status of tasks is represented by grey (empty task), blue (finished task) and navy (in progress) colour.
Grade column (6) shows the result converted into level.
You can also download the results as a spreadsheet (.xls file) by clicking 'Download' button (7).