Using simple words correctly in English is not simple, even though it seems so. Simple words usually have several subtle different meanings.
... as John brought out in the comments.
Why not just brought? Why brought out?
The reason is because brought out has different meaning from brought. Brought out is the past tense of bring out; and bring out is a phrasal verb, meaning "to reveal or expose" or "to introduce (a debutante) to society".
How to know when to use which?
As you suspect, there are no simple rules. Trying to memorize phrasal verbs and idioms could help, though I personally not recommend it. As far as I know, the best way to cope with them is to immerse in the language. This means that you need to listen and read a lot, as well as to speak and write a lot. The more you use the language, the deeper you can develop senses of these simple words, and a better chance to understand them and use them precisely.