first of all.. Welcome to the site. I am assuming you are looking for specific players, sets, etc. needing to fulfill your current sets? One way you can accomplish finding certain cards to purchase is by creating a wantlist. you can simply do this by imputting what you currently have in your collection and then under that sets summary, there is a link to add missing cards to your want list under its summary for that specific set. Another way, create posts like you did here listing specific details of what you are looking for and luckily, someone who has the cards you are looking for will respond. The first option is by far the easiest and allows more control of what you want. by creating the wantlist, you can search for these items within the database as it will list people who have the cards matching your want list to their own sell list. from there, its about making contact with the seller and coming to agreements. Good luck and Welcome again to TCDB!
John Barclay