Try this: read a passage and create a main point-support outline. Something like:

Main Point

- Support 1

- Sub-Support 1

- Sub-Support 2

- Support 2

In the beginning, this will take time (you might have to re-read several times), but it will force you to really think about what you read and it will help you to understand how every sentence in the passage relates to each other.

Really understand why an answer is right. If you can do that for every question, meaning, you understand why A is the clear right answer and why all the other answers are wrong, then I'm certain you'll improve.

Getting questions wrong "randomly" means you got questions right randomly, so just really dig deeper, focus on why you got something right or wrong, and then execute well.