In type 2-3 basically the stool is very hard and you need to use a stool softener like liquid paraffin. Do not use bulking agents or fiber as this will only make it worse.
In types 4-5 you can use a bulking agent like Forlax or psyllium husk or fibre. Irritants like prune juice, dulcolax or senokot will also work, but be careful not to abuse it.
In type 6-7 basically the faeces/stool is impacted and the wattery bits are being sqeezed through the sides of the stool. This will probably need manual disimpaction (look out for the explosive disimpaction)
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p/s: FAQ is updated. You might wanna go read that some times.