Hello Richijun,
If you had a new clutch fitted, did they check that the clutch slave cylinder is OK? If that is worn or leaking, it reduces the amount of movement to disengage the clutch so it doesn't fully release and the gears are hard to engage because the input shaft is still turning. There is a rubber boot over the end of the cylinder, if you peel it back and it's wet inside then it's leaking. Slave cylinders are fairly cheap to replace. The other problem may be the damper valve attached to the clutch master cylinder. If that's faulty it can also reduce the available travel. Also, I hope there's no air in the hydraulic line and it's been bled properly.