"A friend who helps you when you are in need is better than one that congrates you when you are successful." Literally: "Adding flowers on brocade" (錦上添花) is not so good as (不如) "offering charcoal to someone (suffered) in snow" (雪中送炭)

锦上添花 means you improve something which is already good itself. 雪中送炭 means you help someone in need And 不如 means.. It is better to... So it means, rather than adding value to things that is already good itself, it is better to help someone in need(i understand it as helping in something which deserves more attention)