From the movie Ant-Man we know that Janet Van Dyke got inside the missile which was lost in the sea.
The duo undertook many S.H.I.E.L.D. operations, until a mission in 1987 to disarm a Soviet ICBM en-route to the United States. In order to stop the missile, Janet disabled her regulator to shrink small enough to enter the missile and though the mission was successful, Janet was lost to the Quantum Realm.
Later, in the film Ant-Man and the Wasp ,through entanglement with Scott, She manages to send her coordinates and Hank Pym goes in there and gets her.
My question is, how did Hank travel thousands of miles and go to the Pacific Ocean to get her? Considering his size of atomic levels, I believe it must be difficult. Is there a scientific explanation which allows people/things to travel large distances in quantum theory?