Perhaps you should try some spelling variations:
associated infection » associated infections
associated factors » associated bacteria
associated vector » associate director, associated secretory, associated operators
associate editor » associate editors, associate director, associated factor
associate factor » associate director, 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 editor) OR (((associate factor) OR (((((associated vector) OR (associated infection))) OR (associated factors)))))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((associate editor) or (((associate factor) or (((((associated vector) OR (associated infection))) or (associated factors))))))".
• Adding a wildcard symbol may retrieve word variants: ((associate editor) or (((associate factor) or (((((associated vector) OR (associated infection))) or (associated factors))))))*.