E34 and E32 headlights are not sealed 100% and also do not have airation system to let heat out, that is also why one should not install stronger rally bulbs with for eaxmple 100W.
Usually that moisture disappears when the bulb heats up the area inside.
Some people in Germany drilled a 1-2 mm hole at the bottom of the reflector to let the moisture drain out. In my opinion not necessary.