This is the 694th most frequent Bulgarian word.
полза
Benefit; Use; Advantage.
In this sentence, "полза" refers to the benefit or advantage obtained from an effort.
Полза от това усилие ще има, ако продължиш с постоянство.
You will benefit from this effort if you continue with persistence.
Here, "полза" is used to indicate the lack of positive outcome or benefit from significant efforts.
Той вложи много усилия, но без особена полза.
He put in a lot of effort, but without much benefit.
In this context, "полза" means usefulness or advantage that can be derived or obtained in the future.