Perhaps you should try some spelling variations:
associated vectors » associated factors, associated receptors, associated pastors
associated vector » associated factors, associated secretory, associated infection
associate factor » associated factors, associate editors, associated fatty

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((((((associate director) OR (associated vector))) OR (associated vectors))) OR (associate factor)).
• Adding a wildcard symbol may retrieve word variants: ((((((associate director) or (associated vector))) or (associated vectors))) or (associate factor))*.