Repeating tests

I hope I can explain this well enough for someone to answer.

I am doing the Level 3 course and finding some of the tests quite difficult. 
On the sentences that I scored less than Easy, I would like to try them again.
I can see what they are on the pull down menus, but don't see a way to just redo them rather than reset everything.
Is it possible to just repeat the ones marked Hard, So-so, etc. and improve my rating?
Thanks.
 

I don't know of a way to just be quizzed on items we marked hard, but I do notice it brings up the lower rated items more frequently than the higher rated items. That is better than nothing. Perhaps Rocket Languages can add a feature/option where we reset all items we marked hard, etc..

I agree with Robert: I too do not think you can just retake lower rated questions, but it does seem to give you those more frequently. I was wishing just yesterday that I could quiz myself on flash cards that I didn't do well on first time through.