In Miami, the American team introduced its first major upgrade of the season in the form of a revised floor.
Helped by issues for others and a red flag in Q3, Kevin Magnussen qualified a surprise fourth.
The Dane made a bad start and, after doing his best to make it hard for rivals to pass – notably Ferrari's Charles Leclerc – he eventually finished 10th.
Meanwhile, his team-mate Nico Hulkenberg fell from 12th on the grid to 15th at the flag.
Steiner said that the new floor, with the changes focussed on the underside rather than the more visible edge, had been an improvement.
However, he reiterated that the team has to improve the car's performance in traffic.
"It seems to be working," he said of the floor. "We just need to find out what we need to do to get more stable in traffic, that you're not wearing the tyres out this much in traffic.
"Because the guys say, in traffic, they can see the other cars aren't struggling as much as our car, so the guys in the aero department will work on it."
He added: "We have got some parts for Imola, some front wing flaps, not complete wings. And they keep on coming."
Steiner noted that the Miami race highlighted that it's not easy for his drivers to follow other cars without losing tyre performance.
"To get a point is very difficult, and out of five races we've scored three times points, which is not bad," said Steiner of Magnussen's race.
"In the beginning, we were going very well. We dropped a little bit off once we got in traffic and things like this, our pace got a little bit slower. We need to look into that one and what it is.
"But all in all I think when we qualify in the top 10 we can bring home some points. I mean, obviously if everybody finishes it's very difficult.
"In the end we did it, we got a point and that's what it will be this year, just every little bit you can have let's take it home, leave nothing on the road. As much as you want more we need to be happy with what we got."
Steiner said he was pleased to see Magnussen battling with the Ferrari of Leclerc.
"Fighting with Leclerc in the beginning and stuff like this is pretty good," he said "And I think everybody enjoyed that, that is what it should be about. It was good.
"It's just the second half after his battle with the second set of tyres with Leclerc there was a drop-off until he recovered the tyres, and then the other ones behind him had just new tyres.
"But I don't think there was a real threat from them in the end. But you always get worried, one little mistake and you lose to point which is there."
