el quebradero de cabeza - headache in the sense of someone or something that causes concern or bother.Spanish example: Sin embargo, no todo es maravilloso, y tienen serios inconvenientes que provocan más de un quebradero de cabeza.
English example: Nevertheless, not everything is wonderful, and they have serious problems which cause more than a headache.
Source: el quebradero de cabeza - headache in the sense of someone or something that causes concern or bother. (https://www.123teachme.com/spanish_feeds/word_of_the_day/2026/6/7)