cheats for r4

is there any way to get extra cheats onto my r4.
e.g. there aren't any cheats available for pokemon mystery dungeon time so is there a way to get cheats for it?

Yes just download usrcheat.dat from cheats.gbatemp.com
and put it into your system folder

for some reason its got some cheats for some games but it doesn't have cheats for pokemon mystery dungeon 2 :(
does anyone know what to do?

Download my UECheat.dat in my cheats thread, it has all cheats or you could download my YSMenu as well:
https://www.romulation.org/forum/index.php?topic=15544.msg174076#msg174076Also this may be useful:
http://www.cheatcc.com/ds/pokemonmysterydungeonexplorersoftimecheatscodes.html

The ones from cheats.gbatemp.net have already been updated.