Wǒ cházhǎo le hěn jiǔ yě méi zhǎodào nàge wénjiàn.
I searched for a long time but couldn't find that file.
Tips
usage
查找 implies methodical searching — checking databases, files, records. For casually looking for something physical (like your keys), just use 找. 查找 is common in tech contexts: 查找和替换 means 'find and replace.'
