Redknapp has already brought in Richard Dunne, Danny Simpson, Karl Henry, Gary O'Neil and Charlie Austin to boost Rangers' promotion bid.
The unbeaten Hoops havetaken seven points from their first three matches following Saturday's 1-0 win over Ipswich but Redknapp wants to strengthen further, with Tottenham midfielder Scott Parker a target.
"We've made a good start. We're up there and have got some points on the board early," Redknapp told the club website.
"We're still looking to improve the team and build the squad. We're trying very hard and I think we'll do so over the next couple of weeks."
Redknapp has also cleared the decks at Loftus Road with the likes of Jose Bosingwa, Chris Samba, Djibril Cisse and Adel Taarabt moved on.
But one player who was expected to leave, midfielder Joey Barton, has impressed the Rangers chief.
"There's good spirit within the club," he added. "Joey Barton was also top class in the middle of the park. I've been really impressed with Joey's performances so far this season, I must admit. He's a really good footballer."