to trace something back to its origins or source; to date from

to recall or look back upon; to trace something back to its origins

To go or flow against the current; to travel upstream

To trace a river upstream to its headwaters; also used to mean investigating the origin or root cause of something.

To trace something back to its origins through a thorough search; to investigate the root cause of a matter.

to trace something back to its origin; to get to the root of a matter

to pursue something back to its origins; to trace back to the source; to get to the bottom of something

(proper noun) An imperial library building in the Mukden Palace in Shenyang, built in 1782 to house a copy of the [[四库全书|四庫全書|si4 ku4 quan2 shu1]] and other major literary collections.

to investigate the origins of a matter; to seek out the root cause of something

Not to investigate or hold someone responsible for past mistakes; to let bygones be bygones.

to trace back to; to follow something back to its origins

To go against the current; to travel upstream.

To swim or sail against the current; to go upstream.

to engage in mountain stream climbing or river tracing, a recreational activity involving hiking upstream

To investigate the origin and development of a matter in depth

to trace something back to its origins or look back into the past

to trace something back to its origins by going against the current

To go upstream or swim against the flow of water; to travel against a current