Andy suggests:

Some of the low flush toilets have two modes of operation,
which they don't tell you about.

If you push down the flush handle and let it go quickly, only
about half the water goes to the bowl. This is for flushing pee.

If you hold the flush handle down for 3-4 seconds before releasing
it, all the tank water goes into the bown. This is for flushing poop.

My toilets work fine using the pee technique for both types,
usually. But, occasionally,
it is necessary to use the poop technique. One develops judgement
in this area, after a few tries.....

Good luck,

Andy