Villa's clean sheet means that Sunderland have now drawn blanks in four of their last five outings.
O'Neill has conceded that players such as Adam Johnson, Stephane Sessegnon and James McClean, who have all yet to score in the Premier League this season, are struggling for form and thus the Black Cats are finding it difficult to create goalscoring chances.
He said: "It just wouldn't drop for us in the penalty area. We put an awful lot of pressure on them.
"Scoring goals has been a problem for us this season but it was not for the want of trying. Our creative players are finding it a little bit difficult at the moment."
Steven Fletcher is the only player to have scored a Premier League goal for Sunderland this season.