Usually, Chelsea will fight and struggle when meet a strong team and be careless when meet a weak team. By winning on the champions league last night, It does not mean Chelsea will able to win the next match versus Leicester and Everton. As I know, Chelsea is seem not focus on premier league, maybe they searching another way to keep it strong by focus only on champions league.
The thing that must be noted is that winning against small team in EPL was also a very important task caused by when you will not able to win UCL but you are at the bottom position and you will not able to be qualified for UCL next season.
Chelsea is already at the bottom and it needs to take the small team seriously to make sure if Chelsea will able to win and get full points by the end of the season. UCL is the only trophy that can be won by chelsea. I see no chance for chelsea to be qualified for UCL if chelsea keeps losing more and more points in EPL. The good result against leeds didn't prove that chelsea backs on its best performance. Chelsea needs to win a few more matches in a row.