Complex sentence: The Mexican government ignores them, as they are few and located in remote parts of the state; outside organizations that do deal with them find it difficult, claiming their composition changes too quickly to maintain any knowledge of what is in progress.
Split into simpler sentences: The Mexican government ignores them, as they are few and located in remote parts of the state. Outside organizations that do interact with them find it difficult to do so, claiming their composition changes too quickly to maintain any knowledge of what is in progress.