look for, seek, make change
找 centers on actively searching for something or someone, with a secondary sense of making change (as in money), which can be seen as seeking the correct amount to return.
找 combines 扌 (hand) with 戈 (halberd/weapon), suggesting a hand searching or seeking. The exact historical development is uncertain, but the component combination likely expresses the idea of looking for something by hand.
The hand 扌 beside a weapon 戈: imagine a soldier using his hand to search through a pile of weapons, looking for his own halberd.
For ソウ, picture a soldier searching for his halberd and suddenly shouting 'Saw!' (as in 'I saw it!') when he finds it: Saw -> ソウ.
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