informalWRONG/INCORRECT to have a wrong idea, or do something in a way that will not give you the information or result you want 打错主意;认错目标
The police spent three months barking up the wrong tree on the murder investigation.
警方调查这起凶杀案时方向不对头,枉费了三个月的精力。
Examples from the Corpus
bark up the wrong tree• Can't help thinking that they are on the right track and it's we who are barking up the wrong tree.• Could he once again be barking up the wrong tree?• However, those who advocate a federaltakeover of workers' compensation are barking up the wrong tree.• In retrospect it now seems that both camps were barking up the wrong tree.• People who feel sorry for my old bridesmaid and travellingcompanion are barking up the wrong tree.• They have maybe barked up the wrong tree.• You're barking up the wrong tree if you think Sam can help you.