Perhaps you should try some spelling variations:
transfer system » transfer systems, transport system, transit system
a transformer » _ transformer, a transformed, 3 transformer
system prior » system pilot
agua en » agua e
1 macao » _ macao, 2.1 macao
1 macro » _ macro, a macro, 2 macro
en a » en la, e a, et a
heat » head

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: (( agua _ heat transfer system prior ) OR ( agua en a transformer ((1 macao) OR (1 macro)) ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( agua _ heat transfer system prior ) or ( agua en a transformer ((1 macao) OR (1 macro)) ))~".
• Adding a wildcard symbol may retrieve word variants: (( agua _ heat transfer system prior ) or ( agua en a transformer ((1 macao) OR (1 macro)) ))*.