It depends what you need help, if you suggest certain things i can help!

thank's maybe i am old haha! I really think my English is very bad, is looking for a good way to learn.

Yes, some words are less common. It can be difficult to use them often to help remembering them. My daughter's class in school has a large sign "Better words". It is to remind the girls to use more interesting words, not just the simplest words. They are encouraged to make their speech & writing more colourful. Sometimes this is easier when you are 10 years old. :)