Try to make your search as simple as possible:
Dillwynia will find all items including that sequence of letters.
Search results for "Dillwynia":
"Dillwynia ericifolia" - Dillwynia retorta
"Dillwynia floribunda v sericea" - Dillwynia sericea
"Dillwynia retorta v phylicoide" - Dillwynia phylicoides
"Dillwynia trifoliata" - Rothia indica