Perhaps you should try some spelling variations:
cooper jason » cooper john (Expand Search), cooper alan (Expand Search), cooper james (Expand Search)
complex tien » complex times (Expand Search), complex than (Expand Search), complex time (Expand Search)
set complex » set1 complex (Expand Search), yet complex (Expand Search), onset complex (Expand Search)
nabr carlos » jair carlos (Expand Search), mar carlos (Expand Search), aybar carlos (Expand Search)
carlos nava » carlos navarro (Expand Search), carlos eslava (Expand Search), carlos zavala (Expand Search)
tien ngoc » tran ngoc (Expand Search), tuan ngoc (Expand Search), diep ngoc (Expand Search)
nacl nabr » nacl kbr (Expand Search), nacl nano (Expand Search), nacl naoh (Expand Search)
l cooper » j cooper (Expand Search), m cooper (Expand Search)
0.9 nacl » 3.5 nacl (Expand Search)
jason n » jason _ (Expand Search), jason a (Expand Search), jason c (Expand Search)
5 set » 5 sets (Expand Search), _ set (Expand Search), a set (Expand Search)

You can also try:

• Europeana
• Digital Public Library of America
• CORE

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( j l cooper jason n ) or ((( 5 set complex tien ngoc ) or ( 0.9 nacl nabr carlos nava ))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( j l cooper jason n ) OR ((( 5 set complex tien ngoc ) OR ( 0.9 nacl nabr carlos nava )))).
• Adding a wildcard symbol may retrieve word variants: (( j l cooper jason n ) or ((( 5 set complex tien ngoc ) or ( 0.9 nacl nabr carlos nava ))))*.