der Sog
suction
A strong, pulling current in a liquid or in the air that carries objects along with it.
Der Schwimmer wurde vom gefährlichen Sog erfasst und unter Wasser gezogen.
The swimmer was caught by the dangerous suction and pulled underwater.

suction / pull
Loading your saved state.
suction
A strong, pulling current in a liquid or in the air that carries objects along with it.
Der Schwimmer wurde vom gefährlichen Sog erfasst und unter Wasser gezogen.
The swimmer was caught by the dangerous suction and pulled underwater.

'Sog' (suction/pull) is closely related to the verb 'saugen' (to suck). This connection helps you understand the basic meaning of a strong, pulling force.
Der Staubsauger hat einen starken Sog.
The vacuum cleaner has strong suction.
In the literal sense, 'Sog' (suction) is often associated with water or air. Typical phrases are 'in einen Sog geraten' (to get caught in a current/suction) or 'vom Sog erfasst werden' (to be caught by the suction/current).
Das kleine Boot geriet in den Sog des großen Schiffes.
The small boat got caught in the suction of the large ship.
In the figurative meaning, 'Sog' (pull) describes a fascination. It is often media, art, or events that 'einen Sog entwickeln' (develop a pull) or 'einen Sog ausüben' (exert a pull).
Das Buch entwickelte einen solchen Sog, dass ich es nicht weglegen konnte.
The book developed such a pull that I couldn't put it down.
train / move / draft
'der Zug' and 'der Sog' can both have to do with a pulling effect from air or liquid. 'Zug' is often a rather light or noticeable current of air, for example cold air coming through an open window. In addition, 'ein Zug' can also mean a single act of inhaling or drinking. 'Sog' is stronger: a current pulls something along with it or toward it, for example water or air near a moving train. The words can be confused because both describe something pulling. For an unpleasant current of air in a room, people usually say 'Zug'. For a strong force that pulls things along, 'Sog' fits better.

Am Bahnsteig spürt man den Sog, wenn ein schneller Zug vorbeifährt.
On the platform, you can feel the suction when a fast train passes by.
Mach bitte das Fenster zu, hier ist ein kalter Zug.
Please close the window; there's a cold draft here.