Gareth McAuley’s own goal and Victor Anichebe’s second-half strike sealed the three points for Moyes’ side and helped them leapfrog Merseyside rivals Liverpool into seventh place.
Moyes signed Nikica Jelavic in a £5m deal from Rangers in January and the Croatian striker has already netted three goals.
The Everton boss also signed Darron Gibson from Manchester United, while Landon Donovan and Steven Pieenar arrived on loan.
“I think the difference has been the boys we brought in January,” said Moyes.
“They’ve made a massive difference: Landon Donovan, Darron Gibson, Nikica Jelavic, and Steven Pieenar.
“I think that’s why if you look at the team from the end of January, with the exception of Landon who came before them, the difference between now and then.
“It was noticeable even against West Brom to get Pieenar, Jelavic and Gibson on the pitch. It has made a big difference to us.”
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