The Yorkshire giants wasted some great chances in the first half against Fulham on Tuesday night and almost paid for their profligacy after the break.
Leeds finally managed to win the EFL Cup third-round tie on penalties, but Fulham came close to taking the lead on a few occasions in the second half.
They had a similar tale to tell against Newcastle as well at the weekend when they created chances to score more than just once in the first half and the Magpies fought back to get a point.
James conceded that Leeds need to address their failure to make the most of the chances they create when they are on top during games.
He stressed that while Leeds managed to keep Fulham down to only a few decent chances, his team need to start taking their own opportunities in order to win games.
The Leeds winger said on LUTV: “We created a lot in the first half, just like the game the other day.
“That is something we need to work on, we’ve got to score when we are on top.
“The second half was a little bit tougher, but I think there were quite a lot of counter-attacks and we saw the game out towards the end.
“They had a couple of headers that nearly went in, but except that they did not threaten too much.
“We need to keep making those chances and start putting them away.”
Leeds will look to get their league season back on track when they host West Ham at Elland Road on Saturday.
