This is the 16389th most frequent Polish word.
walczącymi
"Walczącymi" - "Fighting" or "struggling" (instrumental plural form in Polish).
Here, "walczącymi" describes the people who are actively struggling.
Spotkałem ludzi walczącymi z przeszkodami losu.
I met people struggling with the obstacles of fate.
In this case, "walczącymi" modifies "tym", referring to those involved in the act of fighting.
Pomagaliśmy tym walczącymi o swoje prawa.
We were helping those fighting for their rights.
"Walczącymi" in this sentence refers to individuals who were involved in fighting for freedom.