If you have to push the work piece harder through the table saw blade and you see ragged, torn, splintered or burnt grain along the edges where you just cut, you may need to clean, adjust or replace the blade. You might also need to clean the table and use a guide to achieve clean cuts.
First, check the condition of the saw blade for damage or residue. Clean gum or pitch residue off the blade using turpentine and steel wool. Replace the saw blade if it's worn or damaged.
Check blade alignment because the blade won't make accurate cuts if it's not parallel with the miter gauge groove. If blade alignment is off, use a combination square to accurately adjust the blade so it's parallel with the miter gauge groove.
Use the right type of saw blade to cleanly cut the work piece.
Clean gum or pitch off the table so the work piece feeds smoothly through the cutting blade area when making cuts.
Use the rip fence or miter gauge to guide your work piece through the saw blade for uniform cuts.