A game away at Wealdstone comes after a late 1-0 win against Concord Rangers, writes Tom Feaheny.
"Until we are mathematically safe, we know we have to use these extra matches to create a bigger gap," Richards told the club's website.
"The job isn't done and we all know that but we are on a good run going into a crucial few weeks.
"It is important that the lads have stuck together, it is all about us getting the best possible results."
City gained victory on Saturday thanks to a late goal in added time from Ed Williams and Richards believes that desire shown is crucial.
"We have played a lot lot better and lost so it is results like that we take them and the last minute win means a lot, we have kept going until the end again."
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