Hey Harley, generally DAWs' have audio interface(s) built in, or they wouldn't be a DAW. A DAW combines A/D D/A converters (which is what audio/digital interfaces do) with inbuilt software/hardware to digitally record, route and process the inputs/outputs. So the 2nd part is what PC programs do (QBase, Protools etc), so software running on your PC hardware. The sound card is the I/O A/D, D/A converter. You can buy (as being discussed here) a better (more expensive, more channels) audio interface.
So simple answer is probably no as your DAW has this I/O already. Can you buy a better I/O device than in your DAW, yes (bring some $s, the more the better), can you use that with your DAW ? depends, generally no, and it would only be an advantage if you can bypass the DAWs analogue inputs and feed the direct digital signals from the I/O into the DAWs software/hardware (eg SPDIF input on DAW if it has one ?? as this is optical/digital and also if the I/O has SPDIF (most do BTW)).
But many aspects are involved in a good quality recording (disregarding the playing here), the first and foremost is what do "you" consider good. Can you hear the difference ? do you care ? Eg if you are making MP3s', ACCs, YouTube clips, it doesn't matter that much as the quality of those formats is so limited (albeit very convenient).
If the I/O on your DAW is pretty limited (eg 44.1khz 16bit (CD qual)) and your DAW can handle (process, record) better sample formats (48khz 24bit is quite usable and I'd describe as what you might consider the start of good quality) and you can sample at that format then sure. But I suspect your DAW won't cope ? Do you have it's user manual, I can check the possibilities for you.