The Briton equalled his career best with fourth place at Sakhir, leading the race for three laps and tantalisingly close to a top three finish before being caught by Lotus's Romain Grosjean in the closing laps.
"We've got to take a great amount of credit and positives from the first four grands prix," the Scot, who was fourth in Singapore last year, told reporters.
"But the team needs to work hard to bring updates because if they want this podium, they're going to have to work for it - probably more than we are at the moment," he added.
"They want a podium. I said give me a faster car and they'll get a podium. If they work a bit harder in the design office and essentially get a bit more resource in there, there's no reason why we can't do it."
Force India beat two McLarens, two Ferraris, two Mercedes and one Red Bull on Sunday and are now fifth overall and three points ahead of mighty McLaren in the constructors' table.
Team co-owner Vijay Mallya, delighted to see his cars filling the third row on the starting grid before the race, did not expect McLaren to stay behind for long but savoured the moment anyway.
The liquor and spirits baron, whose heavily loss-making Kingfisher airline has been grounded for months, held up Bahrain as proof that progress was being made anyway and said he wanted success as much as anyone.
"I am doing my damnedest to get there. I think that we missed out on at least three podium chances last year," he told Reuters. "It isn't as if approaching the podium is something that has only happened now.
"I have not said no to any technical request. (Technical director) Andy Green is fully aware that while I am willing to support him 110 percent he has to be responsible enough not to waste money. We don't have money to waste.
"If tomorrow I put another 100 million into this team, it's not going to guarantee me any performance," added Mallya.
Di Resta, who headed off to Bangalore after Sunday's race for promotional work, looked forward to the next race at Barcelona's Circuit de Catalunya in May which marks the start of the European season.
The team looked quick there in pre-season testing and, with a car that likes hot conditions, should be fast again at the Spanish Grand Prix if the sun shines.
"I think we've performed to the 100 percent maximum we could have done," said Di Resta of Sunday's race. "To go away with all those boxes ticked, credit to all the boys who are working hard."
The Scot's form tailed away last season, perhaps due to disappointment at missing out on a move to McLaren when Lewis Hamilton left, and he recognised that he had let his head drop.
"I kind of convinced myself that nothing was going right," he said. "(This year) was a fresh start and I think we've performed to what we could have... We just keep rolling on.
"We've got some new bits coming that are quite exciting for Barcelona. If they work, it could turn us round. But not all the teams are sleeping and I'm not going to get myself carried away," he added.
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