尋根溯源

see 追根溯源[zhui1 gen1 su4 yuan2]

to search / to look for / to seek

to seek one's roots / to get to the bottom of a matter

root / basis / classifier for long slender objects, e.g. cigarettes, guitar strings / CL:條|条[tiao2] / radical (chemistry)

to go upstream / to trace the source

variant of 溯[su4]

to investigate the origin of sth / to trace a river upstream back to its source

root / source / origin