Samuel Eto'o grabbed a hat-trick for Jose Mourinho's men to give the west London giants all three points.
United are now 14 points adrift of Arsenal at the top, 13 behind Manchester City in second and 12 away from Chelsea.
But, despite their struggles, Moyes insists that their long-term planning will not be replaced by short-term thinking, no matter what their results are.
Asked if he could change his plans to fix their short-term issues, he told Sky Sports: "Not because of results.
"The club know exactly what we want to do and the direction we want to go and the type of players we want to bring to the club and a lot aren't available in this window. If we could get any of them we would do, we are trying but more than likely most people know it is difficult.
"I think the club have always said it is long-term, we know there is a job to be done and we have an idea of players we would like to bring in and we would like them now, but more than likely won't be."
Moyes refused to rule United out of the title race, but admits it would not be easy from here.
"It is a long way away, we will never say it is gone and we will do our best to get back in and the only thing we can do is try and win our next game and we will try and do that," he said.
Talking about the game, Moyes admits whilst his side played well in patches, their defending let them down.
"We got a bit unlucky with the first goal and a deflection but the other two came from set-pieces and that is our own fault and that is nobody else's fault. Terrible defending on the first goal and just as bad on one just after half-time," he continued.
"I thought we played quite well at times, especially in first period but we just lacked that bit. We just needed someone to take on one of their chances.
"I knew the game would be tight, and it was except two set-pieces which has really changed the game. Apart from that I think we have had as many chances if not more than Chelsea. We had done a lot of good things in the game but football is about scoring goals and we didn't and Chelsea did.
"We can only blame ourselves, nobody else."
Moyes did not agree with the late red card for Nemanja Vidic and said: "I don't think it is a sending off, but I just think it is a bit of tiredness.
But Vidic has all but written off United's title defence and told Sky Sports: "We are too far behind and we have now to focus on the top three or four.
"We have to be positive, today we didn't play a bad game. They had three shots and scored three goals and that's the difference in the game, we have been punished for every mistake we made.
"It's not going to be easy, we have to now fight to achieve the Champions League. We have to stay positive and stick together and work hard. With a bit of luck hopefully we can achieve that."
Vidic is refusing to blame Moyes for United's slump in form and says the players are tired of discussing their under-fire boss.
He said: "We cannot always speak about managers, the players are tired of speaking about that because the manager is trying to do the best he can. Tactically we did well today."
@solskjaer99 How about you stick by your team and get on with it. Fergie saw something in Moyes so that should be enough for you. The team he also inherited is dreadful. Give him at least another proper summer window and another season before going awol.- chrissb7