Jamie Vardy's first-half goal was enough to secure three points for the reigning Premier League champions on Saturday.
It is the first time in West Brom's history they have failed to score in five consecutive matches.
"It's yet another game where the players have walked off the pitch certainly not having deserved to lose," Pulis told the club's official website.
"I cannot fault them other than that little bit of clinical finishing that we can't deliver at the moment.
"But we also need a bit of luck
That was epitomised probably by Craig Dawson's header which was on its way but struck Chris Brunt on the back
Their keeper would have had no chance saving that but those are the kind of breaks we're getting at the moment.
"There's no lack of effort, no-one's taking it easy, we've got four games left and we're still determined to hit that 50-point mark - we've not given up on anything yet."
West Brom remain in eighth place, six points off the half century of points Pulis is aiming for.
Vardy's 17th goal of the season puts Leicester on the 40 point mark - in 11th place - but not mathematically safe from relegation although it will take a remarkable set of results for Craig Shakespeare's team to get dragged back into trouble.
Leicester defender Christian Fuchs told the Foxes' official website that it needed a team effort to overcome a tough test in the West Midlands.
He said: "It's always hard to come here
When you're playing against West Bromwich Albion, it's always a hard fight
They're always physical and strong
It was maybe scrappy at times but it's three points and a great win for us.
"It feels good as we also scored
It always helps when we go up 1-0
It was a great goal from (Vardy) and we head home with three points
Obviously, for us as defenders, it is very important to keep clean sheets
When we're able to do that, it gives us a great chance."
Source : PA
Source: PA