Goals from Filipe Morais, Lucas Akins and James Dunne handed Boro their sixth league victory on the road this season.
An impressive second-half performance at Huish Park maintained the visitors' League One promotion charge - and Smith hopes to see more of the same at the weekend when his side host Preston.
He said: "The FA cup game (at Rotherham last Saturday) came at a good time for a couple of reasons - one being to take our mind off the league.
"We're all really disappointed we've been knocked out of the cup but to get back on track with our league form, which has been fantastic, is really pleasing. Three points on the road is not to be scoffed at and this group has done a fantastic job. If we can pull that around a little bit more at home then who knows what is in store for us."
Smith added: "We certainly didn't do ourselves any justice with the ball in the first half, but the second was a completely different picture and once we got the second goal I thought we looked strong."