Try to make your search as simple as possible:
Hibbertia will find all items including that sequence of letters.
Search results for "Hibbertia":
"Hibbertia angustifolia" - Hibbertia procumbens
"Hibbertia canescens (Sieber)" - Hibbertia obtusifolia
"Hibbertia kochii" - Hibbertia rhadinopoda
"Hibbertia volubilis" - Hibbertia scandens