If you are stuck in a particular place on Zelda 2: Adventures Of Link, then maybe these hints and tips will help you out.
If you come across a Red Jar, make sure you milk out the rest of your magic bar with as many Life Spells to heal yourself, then take the Jar to get the most out of it. If you don't have enough magic to cast Life, but you're still not all that healthy, then highlight the Life Spell, take the Jar, and press SELECT like mad. You'll not only refill your life, but your magic will fill up almost to full!
To get the downthrust, go to Mido and use the Jump Spell to get to the upper door of the church.
To get the upthrust, go to Darunia. Find a house with a chimney and use the Jump Spell to reach it. (You'll have to jump on the roofs of other houses to get to it.) Pull a Santa Claus, and you'll learn the upthrust.
Don't always rely on your ability to throw your sword when you have full life. Especially late in the game, enemies won't be hurt by the thrown sword. Learn how to fight in close quarters.
Remember that whenever you make contact with an enemy, you're going to recoil a bit. Keep this in mind, especially when fighting Skull Balls. Also, remember that if you hit an enemy, you'll stun it slightly, and you won't take damage from it while it's stunned.
If and when you beat the game, you'll have the ability to replay it. When you do so, notice that while all tangible items (palace items, Heart Containers, etc.) will be reset and you must find them again, you'll still know all the spells and have the same high level! At this point, the beginning of the game is a breeze. (Also, beating a palace pretty much means an extra life!)
If you want to experience this superiority without beating the game, then do this: Play the game as you would, but take care NOT to clear the palaces. Take the item, but don't beat the boss. Once you've found all the items, learned all spells, and developed your attributes to 8, start playing the game over again. It'll be so easy!