If there is debris caught underneath certain keys, that could make them difficult to press. If the entire keyboard is like that, then that doesn't sound like accumulated debris. You could turn the laptop upside down and gently tap it a few times to try to dislodge debris such as crumbs.  Unfortunately, to replace the keyboard means replacing the entire palmrest assembly. And, as you can see from the procedure in the Service Manual, it's a lot of work. If you live in the US, Parts-People (specialists in supplying genuine Dell parts and repairing Dell computers) offers a laptop $100 Diagnosis and Repair service, whereby you pay just $100 + parts for repair, with free return shipping. If, after receiving their parts estimate, you decide against the repair, you pay just $30 for their diagnosis + return shipping cost. Whenever touching components or working inside a computer, wear a grounded wrist strap, also called anti-static wrist strap, ESD wrist strap, or ground bracelet. It's a cheap and sensible precaution. Rest the laptop on an anti-static mat or at least a reasonable alternative such as corrugated cardboard. (Repeatedly touching a metal case part is not sufficient mitigation with modern components.)
hi,   My Vostro 5590 is 3.5 years old and some of the keybaord keys barely work, i need to press them harder to make them work. I barely used the laptop as laptop, it was mostly used as a desktop and was closed almost all the time, is there a connection between this facts?   is there any soluction or some way to fix it? since i didn't find a way to replace the keyboard
Vostro 5590 - some keybaord keys barely work