Pressure washer drain cleaning?

[tight fart]

I've got a petrol pressure washer that has some oomph and I want a drain cleaning hose attachment, the lance has a M22 thread.
Now I did buy a 10m hose but its next to useless, it doesn't allow enough flow to do the job, i suspect the internal dia is to small.
Can anyone advise what I should be looking for?

It has a fitment like this.

[Peanut Gallery]

My pipe cleaner for the jetwash has one hole pointing forwards, then 3 or 4 pointing backwards. These are enough to pull the hose into the drain by itself, does a decent job, although I have not yet successfully cleared a drain using it - was a good foot long section of compacted stones and sand.

If I had more time I could have done some, then emptied the end of the drain I could access, then done some more, then emptied more - having it blast dirt back towards the end of the drain does have its uses - and can give the operator a good face-full of whatever was in the drain.

[Snow and Rocks]

Be careful - I bought a 25m one years ago and set about clearing a clogged land drain that ran under an area of the garden. It made steady progress pulling itself along and then stopped and wouldn't move an inch, in either direction...

Tried for hours to free it without success and eventually resorted to pulling it out with the pickup - it snapped and left about 10m underground and the drain still blocked so ended up digging it all up and starting from scratch!