The Ukrainians have scored just three times in four matches but remain in with a chance of qualifying for the knockout stages with two games to go.
They host Real Sociedad on Wednesday looking to improve on their third place in Group A and their poor record up front.
"We have in our first-team squad - in midfield and in attack - probably the youngest players in the Champions League," he told a press conference.
"Goals, unfortunately, cannot be scored due to talent alone.
"They are often scored due to a lot of experience, unfortunately our players do not have that much of it.
"Except, perhaps, the match in Leverkusen (a 4-0 defeat) we played very well against all of our rivals and had the advantage.
"Unfortunately our finishing is not perfect yet - this is our problem.
"I wish we could play tomorrow at least on the same level as we did at home against Man Utd (1-1) and Bayer (0-0) with lady luck shining on us a bit."
Sociedad, without a win, realistically have to set their ambitions at qualifying for the Europa League with a third-placed finish.
However, forward Chori Castro insists they have not given up on their slim chances of making the knockout stage if they win their last two games and other results go their way.
"Let's go with the thing in mind that it's not impossible," he said at a press conference ahead of the trip to Ukraine.
"We will need to remain calm," the Uruguayan said.
"There's no point going crazy from the off because if you go behind against this type of team, it's very hard to turn things around."