The stalker_cop_increase_knife_range.rar file you have requested: Call of Pripyat / Mods / XoBaR's Increase knife range - 3.49kb is not available. Perhaps try browsing all files for the game S.T.A.L.K.E.R.: Call of Pripyat and upload any files you want to share or are missing. This is the only information we could locate:
This mod is designed to increase the range of the knife, only for the secondary attack (right click). Indeed the secondary attack of the knife often fails, due to the physics boxes of the enemies which are too large.