Before you jump in, read this!
For combat, you need to learn the system, and once you master it enemies go down easily. Swipe your mouse when you strike with your sword to slice in the direction you choose - this can be important for hitting enemies.
Enemies will almost always block your hits when they can, but they do also dodge away, which they do immediately before attacking you. This telegraphs the attack, and you can then time a parry (block (MMB) at the right timing), which stuns the enemy and opens them up to rapid, uninterrupted attacks.
It is also possible to hit enemies mid action, such as during longer attacks of theirs, when they are dodging, etc.
Getting hit always breaks your block, so you have to remain vigilant.
So long as you keep moving, keep dodging, keep blocking, and pay close attention, you can win these fights - but only with your skill; the game does not hold your hand.
Electric daggers instantly stun the enemy to open them up, so keep them on hand if you find any. There's a cache of throwing daggers on a table behind you in level 1 when you spawn. Shadow daggers do a lot of damage and disintegrate the body so other enemies can't see it, but they're rare.
Good luck, and have fun!