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That would probably, in your case, be a setting in the printer's driver settings.
In a Windows computer, the driver settings are in
Control Panel - Devices and Printers
then find the icon for your printer, right-click on it, and choose Properties.
There you should find a setting for 'Quality' of print: High Quality would be what you are looking for. Or even, if you are printing in Draft Quality, you might find Medium Quality is good enough, and surely an improvement.
Once you have changed that setting, click on OK until the Properties sheet for the printer closes, in order to make the changed setting effective.
(In an Apple computer the driver settings are differently placed, but the ultimate goal is similar: improve the Quality of print setting.)