If you have the sound xiang but not the character, here are the 4 characters read this way: 相 (xiāng, mutual, appearance, to examine, minister), 香 (xiāng, fragrant, delicious, incense, popular), 想 (xiǎng, to think, to want, to miss), 向 (xiàng, direction, toward, to face, all along). They split across 3 tones, so the tone is what separates them.