Complaint
noun
A paragraph in writing is what you send someone when you want to submit a complaint. You want to make sure these are in writing, though, otherwise you don't have proof of your complaint. Also, don't make it longer than a paragraph, because that's too long and nobody cares about how you think the shop staff mistreated your dog Fluffy.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
彼は何かにつけて文句を言いたがります。
He always wants to complain about something.
そのレストランの料理には文句のつけようがありませんでした。
I could not complain about the food at that restaurant.
それは口説き文句でしょ？
That's a pickup line, isn't it?