Make ferret only search for whole words?

In my app i use ferret to link results from disparate surveys, by name.
Mostly this is working really well: if i get multiple results, i use the
first (ie the closest match), which generally seems to be the best one.
In one example though, the top result isn’t the right one: a search for
“Tanishi Nishi” returns, in this order, the records with names [“Ta
Nishi”, “Tanishi Nishi”].

In other words, the exact match is being beaten by a record that has one
of the names split.

Is it possible, when doing a ferret search, to tell it to only match
whole words, or some other option that will make sure i get the right
result back here?