Conversation so far:
what sort of powers did Drusilla have?
Drusilla has all the standard powers and vulnerabilities of a vampire, plus minor psychic abilities.
What  do her abilities allow her to see?
She receives vivid visions that contain possible glimpses of the future, and can also see into people's minds and project false imagery into them .
do her powers help her hunt vampires?
CANNOTANSWER.

Question: what are her powers used for?
Self-contained rewrite: What are Drusilla's powers on Buffy the Vampire Slayer used for?