"We had scheduled also some interviews and hope we could use your help again."
This is awkward and temporally confusing... had is the "past", hope is for the "future", and could is "possibility".
Since the phrase "could use your help" is anticipatory, the word "hope is superfluous.
Example: We have (also) scheduled some interviews and could use your help again.
Although technically not incorrect in the usage, the word "some" may be unnecessary: either there are interviews, or there are not, the "some" adds no semantic value. If you need to qualify a number, or set of, interviews, then a stricter construction would be "scheduled several interviews" or "scheduled a number of interviews".
The word "also" should only be used if the interviews are scheduled in addition to (or following) some other activities, as opposed to being scheduled independently of any other activities.
To summarize, depending on the nuance of what you want to say:
1. We have (also) scheduled some interviews and could use your help again.
2. We have (also) scheduled interviews and hope we may use your help again.
3. We have (also) scheduled interviews and trust we may use your help again.
4. We have (also) scheduled interviews and hope we can (or may) count on your help again.
:)IdF