It could help if you explain exactly what arrangement you are using
with the flashes, but here's something I suspect:

       The flash you linked to is a digital slave, intended to work with
point-and-shoot digital cameras that use a pre-flash. The pre-flash is
used for two things: either red-eye reduction, or metering the flash
output so it's at an appropriate level. Both of these are done before the
main flash, where the shutter is actually open and the camera captures
the image.

       So, in order for the slave flash to avoid discharging for these
pre-flashes when it wouldn't do any good, it delays 200 milliseconds
after detecting that first flash, presumably to go off when the shutter
is actually open. You can see this in the Features tab at the page you
linked.

       If you are using this flash with a camera that does not use a pre-
flash, the slave will go off 2/10 of a second after the camera flash,
which is usually far too late, and the shutter is already closed.

       Check the instructions. If the slave has an option to fire
immediately rather than with a "digital" delay, use that. If it does not,
it may not be able to be used with your current arrangement.

       You might also look at these units from B&H, which will not have a
delay and will discharge as soon as they detect the on-camera flash (just
paste them into the search field on B&H's site):

       SMPG160S
       ME36C2
       SMMSD
       MOACS2

       I use both of the last two. They are dependable and inexpensive,
but note the guide numbers for their light output - it is markedly
different. Also, buying the bracket/socket for the MOACS2 helps a lot.
      
       You can also buy attachments that turn any standard flash unit into
a slave, such as KASHS and WEFSV283. The latter one is intended for
Vivitar 283 and 285 units, which are a great investment - powerful and
very adjustable.

       You can search B&H by simply typing "Slave flash" into the search
field, but you may also want to do some web research on slave flashes (or
slave strobes) to see what would work best for your situation.

       Hope this helps. Good luck!
      

    - Al.