I would like to dynamic attach text between Word files.

For example, I have investment title in one file and I would like to put this title somewhere in other files and when I change this title in source file it would automatic change title everywhere where this title is attach. Is it possible to do?

Yes, it is possible. However, first look into the AutoText feature build into Word to hold your text and using AutoText fields in your destination documents to show your text.
See Automated Boilerplate Using Microsoft Word