The phrase “expression in one’s eyes” is not one that I have ever heard. In the US at least, “expression on one’s face” is common. Either way, an “expression” generally has a different meaning than “glare” or “glance.” “Expression” has to do with how one’s face/eyes reveal how a person is feeling on the inside. Examples: “He had a sad expression on his face.” “Her expression concealed her true feelings.” “Glare” means “to look at someone angrily.” “Glance” means “to look at something briefly.” So, better synonyms for “expression in one’s eyes” would be “the look in one’s eyes”, “the look/expression on one’s face,” “countenance” (a bit old-fashioned), or “mien” or “visage” (both very old-fashioned or poetic).