4 letters:
ca c, ca v, covy

5 letters:
bethe, bovee, buffi, buffy, busey, bushy, busky, bussi, bus c, buzzy, ca si, copse, covey, cuffy, cushy, deci-, deshi, ducey, duffy, guffy, gushy, gussy, puffy, pushy, pussy, tushy

6 letters:
bushee, bushey, bushie, bussey, bussie, bus he, ca see, cuffee, cushey, does e, dove e, duffee, duffey, duffie, duthie, guffey, gussie, tousey, tussey

7 letters:
bush he, bus see, buzz he, does he, dove he, puff he, push he

8 letters:
bush she, push she, tough he