Ronny Deila called on his players to be more clinical after Celtic surrendered an away lead in Europe for the fourth time this season in their with Astra Giurgiu.
Stefan Johansen's first-half strike had put Celtic in control in their Group D match in Romania, but William de Amorim levelled for a point in 79 minutes.
"I think we have something to work on when we get 1-0 up," said Deila.
"We should just keep on playing and be offensive."
Celtic led Legia Warsaw through Callum McGregor's early strike in the Champions League third round qualifying 4-1 defeat in July.
The same young Scot put Celtic ahead in Slovenia only for Maribor to draw level in the 1-1 draw in the Champions League play-off first-leg, and Mubarak Wakaso had Celtic in front in the 2-2 draw in Salzburg in the Europa League.
Again, they were pegged back in foggy Giurgiu, though goalkeeper Craig Gordon could not be faulted at de Amorim's wonderful equaliser before Astra's Vincent Laban was sent off in injury time for a shocking challenge on Charlie Mulgrew.
"I think we controlled the game quite well. Maybe we could have attacked more and got the second goal," said Deila at the media conference afterwards.
"We had chances to kill the game and win 2-1 but it was not enough today. I think we tried to win 1-0 when we should go for more.
"We didn't have too many chances against us. The performance was OK but the result should be better.
"In the end it was a point. I am not happy with that but it is better than nothing.
"The goal came out of nothing. It was just a fantastic shot from the wide area in the 18-yard box."
His comments were echoed by Mikael Lustig, the Celtic right-back.
"Away from home in Europe if you create so much you need to score more than one goal," he said.
|Celtic manager Ronny Deila|
|"We have two difficult matches left, of course, but we are in a better position now than we were before the game."|
"The last couple of games we created more chances than we did before and in Europe it's a different type of game, especially away from home.
"You need to be clinical, when you get the chances you need to put it in the net."
Deila sent on Leigh Griffiths on for the ineffective Stefan Scepovic for the last 18 minutes and the former Hibernian striker was soon involved in the penalty area.
He was denied by a fine close-range save from Silviu Lung and moments later had a goal ruled out for a slight shove on Astra defender Cristian Orso before he found the back of the net.
"I have not seen it [again] but the player said he didn't do anything," the Norwegian added.
"We should have had 2-1 but sometimes that happens and we have been lucky some other times. This time it has gone against us."
The result leaves Celtic in second spot in Group D, with eight points from four games.
They trail their next opponents, FC Salzburg on 27 November, by two points, but are five clear of Dinamo Zagreb, who lost 5-1 to the Austrians on Thursday, a win that takes them through to the last 32.
"We have two difficult matches left, of course, but we are in a better position now than we were before the game," said Deila.