The Hammers have won just once and lost 12 times from 19 away matches and the Italian was again critical of his team for failing to perform away from Upton Park despite a positive start.
"I thought in the first half we were the better team," said Zola.
"But then they scored the first goal. In the first 15 minutes after half-time they scored a second and after that we played better.
"But it was not enough and I am disappointed because this season away from home, we have not been very good.
"The last week has been great because we got the points we needed and achieved our task. I wanted to focus on the football because that is something we have not been unable to do.
"We came here to win but it did not work out. It is not the first time away from home. We have to do better.
"I don't want to look for excuses. We have not been good enough away and I am the first to take responsibility for that."