can you explain these sentences for me?

[maxleaf]

"To those who understand life,that would have given a much greater air of truth to my story."
"I fumble along as best i can,now good ,now bad,and i hope generally
fair-to-middling."

can you explain these sentences for me?especially the underlined parts,thanks a lot.

[Tdol]

1 It would have made the story more believable.
2 The person does what they can and sometimes it works, but other times it doesn't.