Your printer head need regular cleaning to perform well and last longer. Here's the safe way to do it without damaging sensitive components.
Go to your printer settings and run the automatic head cleaning utility. Run it 2-3 times if print quality is still poor.
If automatic cleaning fails, power off and unplug the printer. Remove the ink cartridges, then remove the print head according to your printer manual.
Place the print head nozzle-side down in a shallow dish with half an inch of warm distilled water. Let it soak for 10-15 minutes.
Dampen a lint-free cloth with isopropyl alcohol and gently wipe the nozzle plate. Do not scrub aggressively.
Blot dry with a clean lint-free cloth. Let air dry for 15 minutes. Reinstall the print head and cartridges. Run a test page.