Multiple bursts of flash to increase exposure.
Just some additional to keep in mind. If the room you are shooting in has lights that are difficult to switch on & off you can meter for the ambient exposure and use it a base exposure. Say f22 @ 1 minute. You can then determine the number of pops you need Say 4 pops. Set your time as 15 sec. ( 15 sec X 4 = 1 minute) Now your ambient is properly exposed as are your strobe exposures. This also works if you have window included. This concept is also useful if you have mixed light sources - say fluorescent & tungsten & strobe. Do the fluorescent turn them off, do the tungsten turn them off & do your strobe work. Alternately you can add the strobe to the individual shots with the others if you have the filtration for your strobe heads. It can get interesting !! To fine tune your exposure you can fire your strobes say 4 times overall & a couple of heads only once or twice as needed.
Good Luck - Once you do it it will become clear & easier.