It's the name of a song and it's hard to understand. Please translate this to simple English.
There Must Be More to Life Than This
It's a bit like "We must not be seeing all of the picture." or "There must be something we are missing. But it is applied very broadly.
Someone who is looking at life--and sees it as routine and negative--with news headlines that are distressing, could use such a phrase to justify a religious belief. "As miserable as I am and am perceiving things, I need to believe that there is a just God and some kind of better future to look forward to."
Then again, it doesn't need to be that broad or metaphysical. Someone might use the phrase specifically in reference to their individual life...maybe they feel their job is a dead-end, haven't had good relationships, feel unhappy. They could just mean "MY life is not satisfying me, and there has to be some chain of events that could lead me to be happier, rather than die with no day being better than the kind of boring day I had"
So you have to use context to determine. Individuals may use the phrase where "this" refers to some annoyances about their personal situation. Artists will more likely invoke this kind of phrasing more generically but with a sort of a calling about an unseen layer of reality that eludes us.
For instance, some nice music with similar construction:
MJ's song is quite touching.
Here, the pronoun this is used for the following nouns in stanzas. If you look at the lyrics here, the pronoun is replaced by nouns like 'killing' and 'living' in coming lines. He wanted to make it generalized in the beginning of the song and thus kept this there.
Paraphrase it this way -
There must be more to life than killing
He is concerned about man killing man and asks for a peaceful world. Simply say, he tells those barbaric people that there is more to life than what they are doing for no reason.