Indeed! The encryptions of the client queries are fully semantically secure - under relatively solid lattice-based cryptographic assumptions, a server would need to do more than 2^128 work to recover the plaintext of someone’s query. One query for one item in the database is indistinguishable (without the client’s key) from another query for the same item later; in other words, it’s similar to something like the guarantee of CBC or GCM modes, where as long as you use it correctly, it is secure even if the attacker can see many encryptions of its choosing.