Three short lines carry a whole morning of missing someone. The speaker has spent hours "in books and other places," which suggests reading, but also wandering through anything that might offer distraction or comfort. Yet the search seems to turn up one thing: "a far face." We never learn whose face it is, and the poem doesn't say. That blank leaves room for any kind of longing, for a lover, a friend, a person lost, or someone simply out of reach.
The word "far" does a lot of work. It points to physical distance, but it can also mean emotional or even temporal distance, a face that belongs to the past. The phrase "all morning" makes the feeling sound steady and patient, not dramatic. The mood is quiet, a little wistful, and very still. The poem is so spare that the face seems to hover at the end of the last line, the way a person you miss will drift into whatever you're doing.