For some of the
cheats you have to get creative in how you go about the search.
For one hit KO, I always start with a boss. At the start of the fight he will have full health, so I start the initial fuzzy search with initial value unknown. Then, each time I hit the boss I apply a decrease search against the latest value. Keep up this procedure and you will be left with a handful of possible address. At least one of these address will define the bosses health, so you have to modify each address individually while returning to the game to see if any changes occur. Once you find the correct address (or addresses), you are golden.
In Ninja Gaiden Sigma plus 2 for example, the address for boss health is found to be 81D4EC9C. We can than use a "Pad" function to assign the Vita buttons to perform a certain action:
_V0 1 Hit Kill Boss
$C201 00000001 00000300
$0200 81D4EC9C 00000000
The code starts at $C201 and states "when ps vita buttons (00000001) R1 and L1 (00000300) are pressed, set the value at address 81D4EC9C to zero".
The process is similar for regular enemies, as their health values are also stored in an address somewhere. In this case, it's best to use the weakest weapons against the strongest enemies to find the address, since this will give you the most searches. If you already have a cheat for health, this will help you here.
Speed movement is a little more difficult because you have to find section of the game that speed up or slow down the character. (This is made much easier if you can find an item that modifies your speed, for example). Once you find one of these areas, you have to again start with unknown initial value and use "increase", "decrease" or "equal to" repeatedly, (using the appropriate search type depending on how the time is shifting). You also may have to reload the game several times, keeping your search results intact, to give you more opportunity to weed out the incorrect address.
Just play around with the searches a little bit and come up with creative ways to find address. You'll be surprised at what you will stumble on!