I don't know why you felt it necessary to post this 3 times, but here goes.
Bloodseeker would only be able to apply the drained 1 condition total to an enemy unless it's ability specifically stated that it stacks further. Remember that unless otherwise stated conditions do not stack with the same condition.
This is still fairly strong as it reduces the enemies effectiveness and gives the bloodseeker the ability to do 2d4 damage without having to roll any to hits. It also gives the bloodseeker that little bit of extra staying power in the form of it's temp hit points that it gains, though again they do not stack.
Primary Source:
REDUNDANT CONDITIONS
You can have a given condition only once at a time. If
an effect would impose a condition you already have,
you now have that condition for the longer of the two
durations. The shorter-duration condition effectively
ends, though other conditions caused by the original,
shorter-duration effect might continue.
For example, let’s say you have been hit by a monster
that drains your vitality; your wound causes you to be
enfeebled 2 and flat-footed until the end of the monster’s
next turn. Before the end of that creature’s next turn, a
trap poisons you, making you enfeebled 2 for 1 minute. In
this case, the enfeebled 2 that lasts for 1 minute replaces
the enfeebled 2 from the monster, so you would be
enfeebled 2 for the longer duration. You would remain
flat-footed, since nothing replaced that condition, and it
still lasts only until the end of the monster’s next turn.
Any ability that removes a condition removes it
entirely, no matter what its condition value is or how
many times you’ve been affected by it. In the example
above, a spell that removes the enfeebled condition from
you would remove it entirely—the spell wouldn’t need to
remove it twice.