Zamora started his first game since late October in Saturday's 2-0 home defeat by Manchester United before being replaced by the returning Loic Remy in the second half.
QPR's tally of 19 goals in 27 games is the lowest in the Premier League and Redknapp outlined the importance of his two strikers to the club's survival prospects.
"Bobby's hip wasn't too bad today, but he did his ankle right at the end of the first half," Redknapp told Sky Sports. "His ankle went up like a balloon at half-time, but he wanted to go on.
"If we can get Bobby out on the pitch and get Remy playing with him as a pair, it will give us something we've really lacked.
"There's no one better in the country (than Zamora) at bringing people into play. We need to play quality balls up to him and get people to join him, and get people into the box to score goals.
"We're short of goals. 19 goals all year is not going to keep you in the division."
The loss to the Premier League leaders left QPR seven points from safety with 11 games to play, but Redknapp is not conceding defeat in the battle to stay in the top flight.
He added: "I think it depends a lot on if I can get Bobby fit and playing. Remy gives us something to hang on to and we've got to try to score some goals.
"I don't think it's impossible. Other people will say I'm crazy to think that, but I think there's a chance. And while there's a chance, I won't be giving up and will make sure the players don't give up."
Jose Bosingwa featured for the first time since early December after he was fined by the club for refusing to sit on the bench against Fulham before Christmas.
Redknapp said of the former Chelsea full-back: "It's all forgotten, we move on. He had a problem and we fined him a couple of weeks' wages.
"His attitude since then has not been a problem. We can't spend the next two years not playing him. He gets paid, he's here to play and he's paid his punishment, that's the end of that. I thought he did okay today."