Perhaps you should try some spelling variations:
"dioxide emission" » "dioxide emissions", "oxide emissions"
"bvoc emissions" » "bvocs emissions", "bvoc emission", "voc emissions", "bion emissions", "bvocal emissionss", "b7 emissions"
"voc emission" » "ion emission", "vocal emissions", "7 emission"

Try widening your search to All Fields.

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: (((("voc emission") OR ("bvoc emissions"))) OR ("dioxide emission")).
• Removing quotes may allow a broader search: (((( voc emission ) or ( bvoc emissions ))) or ( dioxide emission )).
• Adding a wildcard symbol may retrieve word variants: (((("voc emission") or ("bvoc emissions"))) or ("dioxide emission"))*.