This is the 4578th most frequent Polish word.
ludziach
"People" (locative form of "ludzie").
In this sentence, 'ludziach' is the locative plural form meaning 'about the people,' used after the preposition 'o' which requires the locative case.
Rozmawiamy o ludziach, którzy tutaj mieszkają.
We are talking about the people who live here.
Here, 'ludziach' is used to indicate 'with people,' aligning with the locative case that the context dictates.
Nasze złe doświadczenia z ludziach były nauczką.
Our bad experiences with people were a lesson.
In this example, 'ludziach' is in the locative plural form and functions to describe the subject of obtained information, dictated by the preposition 'o'.