I agree with all of the above about not worrying about complex, scientific words. Instead, focus on writing simpler sentences. Make sure each is a complete sentence that contains a subject, verb and object. Eliminate unnecessary redundancy, as it will often confuse the reader. As you gain more confidence, you can add complexity to your sentences, as long as they contain a subject, verb and object and don’t have redundancy.
For instance, here is a sample re-write of your earlier post.
Good evening, users.
I am almost 30 and I want to strengthen my English, due to my not being a native speaker.
I’ve been reading some geology and chemistry eBooks. Some names are very hard, especially the longer names.
For example, for words like these, I installed a Chrome extension that reads the word aloud when it is highlighted. I’ve been using this for a while to learn how to pronounce complex words.
(screenshot)
Can you recommend any other methods that might be helpful?