Is it impossible to use past participle phrase behind the noun to modify?

In a grammar book in Korea, it's not possible to use past participle phrase such as "Jenkins Associates is one of the most noted law firms specialized(x),[specializing(o)], in real estate and business law."

Could I know why the principle happens? And additionally, Could I use the sentence "The leaves fallen from the tree is beautiful"? The reason I wonder is that present participle and past participle have a bit different meanings each such as "-ing means to keep doing or going or p.p means being completed."

Thank you for your time to think over my topic. I hope you all have a great day:)