For SC people suggest
Manhattan GMAT SC book , it's very good you should get one. Also try to answer the question in the verbal section of this forum , u will learn a lot .
As you mentioned knowing where u went wrong is more imp than doing tons of them and not knowing your mistake . Create an
error log and after every test write down your mistakes and try not to repeat those again . keep reviewing it once a day . That will help too .
Master OG , go through their explanation , even u get the question write .
You can also create notes from there , that way u will know more about their objective.
For RC you can read
editorial section on times,scientific american (
https://www.sciam.com/) ,washington post , but remember read the editorial section .
Plus browse through form you will find lots of material for SC , contributed by many users .
Work hard on verbal and you will get a very good score next time . Your quant score is really good, so no worry there .
Good luck .