Bottas leads five times world champion Hamilton by a single point after four races, with both men having won twice each this season.
The Finn, whose advantage stems from a fastest lap in Australia that was worth an extra point, failed to win a race last year while Hamilton was triumphant 11 times.
“This year he has my number two engineer…and he is learning a lot from that,” the champion told reporters at the Spanish Grand Prix. “That’s to be expected, the little bit of a step that he’s taken.
“I’ve got a new engineer and we are working really well together but it takes time to build relationships with people and to continue to grow.
“When you take one element away, whatever element you take away, initially it’s not as strong as something you have built over six years.
“We are building back to being stronger and trumping that. It’s only been four races, so just watch this space.”
Bottas was fastest in both practice sessions at the Circuit de Catalunya on Friday, with Hamilton ending the day second quickest.
The Finn’s previous race engineer Tony Ross left the Formula One team at the end of last season to lead the engineering side at the Mercedes HWA Racelab Formula E outfit that is due to debut later this year.
His place was taken by Italian Riccardo Musconi, previously Hamilton’s performance engineer.
“Whenever you have new people around it makes you think about some things differently,” Bottas told reporters.
“It can open up some new routes on the set-up and the direction. It has started really well. We have been learning a lot as an engineering team all the time and it’s getting better and better.”
In 2016 Hamilton was unsettled when the team switched five of his mechanics to Rosberg’s car, while others went in the opposite direction.
Hamilton felt Bottas, who joined Mercedes in 2017 after 2016 champion Nico Rosberg abruptly retired, had also become more focused.
Formula One champion Lewis Hamilton says Mercedes team mate Valtteri Bottas has been given “a nice helping hand” by one of the Briton’s long-term race engineers crossing the garage to work with the Finn.