If you are trying to index Web 2.0's created with software like Money Robot, GSA or something similar, indexing rates will most likely be very low. This is because these sites are highly spammed. Hundreds of thousands of spammy pages are being created on the same small amount of domains. 

Google uses crawl budget to determine how often to crawl domains and Google will only crawl the same domains so many times per day. We also noticed in March of 2018 that google seemed to intentionally lower the crawl budget for these type of domains due to them being known as highly spammed domains.