You may need to go through your hubs and optimize them. Also you need to do hubs on topics people are searching for and want to read so do some keyword research.
also keep in mind that hubs earn more the longer they've been published so there is a need for patience.
I have 42 hubs and have made way more than you this month. I also routinely update them, ensure I have good summaries, proper keyword usage and I backlink my hubs as well.
When you write and publish you have to do more to draw traffic as well. Don't give up on it too soon. You may also want to write for other sites - like have a blog etc. and link your hubs/blog to each other as well. This generates more income/traffic for both places.