Create a recordset

from a table with fields userID and Date (in which any userID has multiple records with different Date values, and other fields) i have built a select query based on Date = one specific value. can anyone give an explanation (for beginners), through a sample code, that expands the query recordset so that the new recordset includes all records per userID that qualified in the prior recordset? below is an example. thank you!

Table with records:
userID / Date
u1 / d1
u1 / d2
u2 / d1
u2 / d2
u3 / d2
...
1st Select Query (where Date = d1):
u1 / d1
u2 / d1

Desired 2nd Query based off 1st Query (where ?):
u1 / d1
u1 / d2
u2 / d1
u2 / d2