How should I react if my supervisor for my master thesis gives me low quality supporting information?
Working with a supervisor is like working with a manager.

In both cases, they can only help you as well as you empower them to help you.

Ask yourself about previous 'help' moments you required from your supervisor:
what went well and not so well about it?
why was it not as helpful as you wished it would be?
how can you help your supervisor be more efficient and effective at helping you?

More often than not, things boil down to communication issues. 

You need to provide all the information that you have and that your supervisor may need to help you. You also need to be able to convey to your supervisor what you expect from what they will help you with.