Your query will still be a cross-partition query. For example, if you partition by TenantId -> UserId, and provide only the UserId in the query, this query will fan out to all physical partitions.
To have an efficiently routed query using the TenantId -> UserId example, there are two options:
Provide the TenantId. Queries will go to all physical partitions containing the TenantId data.
Provide both the TenantId and UserId. Queries will go to the single physical partition containing the TenantId and the specific UserId.