Most databases allow you to mark a record, or save it into a folder, so that you can easily find it later.
How you do this varies from database to database, but it usually involves ticking a box, or clicking on an icon or link. You can usually select records individually or in multiples. Sometimes you can select a whole page of records, or all the records in the results list.
When you save records into a folder, this will usually be cleared when you log out of that database or database platform.
If you want to save records permanently, you have to set up a personal folder or account. This is free, and worth doing if you expect to use the same database or platform over a period of time. This personal folder/account is usually also required to save searches and set up alerts.
You can find out how to do set up a personal folder/account from the help screens of the database you are using.