This is the 14378th most frequent German word.
irgendwelchen
"Any" or "some," referring to unspecified or random things.
In this sentence, 'irgendwelchen' refers to unspecified books where the speaker might have encountered certain information. It implies that the specific books are unknown or random.
Ich habe in irgendwelchen Büchern davon gelesen.
I read about it in some books.
Here, 'irgendwelchen' is used to refer to any suggestions that could contribute to the project. This usage is inclusive and seeks randomness or availability, indicating openness to any input.
Hast du irgendwelchen Vorschläge für das Projekt?
Do you have any suggestions for the project?
In this case, 'irgendwelchen' describes unspecified restaurants, emphasizing the caution in choosing because the quality and experience are uncertain in random choices.