The dignity of movement of an iceberg is due to only one-eighth of it being above water.
A writer who omits things because he does not know them only makes hollow places in his writing. A writer who appreciates the seriousness of writing so little that he is anxious to make people see he is formally educated, cultured, or well-bred, is merely a popinjay.
Whether you're writing essays and reports or the great American novel, Hemingway's advice is worth keeping in mind. Effective revision often means cutting material from a draft, not adding to it.
And what should be cut? Empty introductions, for a start, and needless repetition, followed by anything that's obvious or irrelevant--information that readers already know or don't need to know.
Then you might reconsider your purpose for writing. Are you consistently informing or entertaining your readers, or at some point have you lost track of your original aim and started showing off or talking to yourself?
Finally, read your work out loud. If you hear yourself chattering like a parrot, cut off that annoying popinjay. Focus on key points and your readers will appreciate the effort.