It is not very easy for a working mother to find day care to look after her children while she is working.

day 的意思是"白天、日间"，这里指"白天时段"。 care 的意思是"照顾、照料"，指对儿童或老人的看护服务。 day care 是一个固定搭配，指"日间托儿服务"，即在白天父母工作时提供儿童看护的机构或服务。