Mortgage underwriters normally want documentation attached to the letter of explanation. For example, a letter of explanation may be required if a mortgage loan borrower had a substantial low income one year from the previous year and had a late payment history for three months.
Wage garnishment by itself will not damage your credit...and the fact that your wages are being garnishment will not be noted on your credit report....However, the judgment that led to the garnishment (if they report it) will affect your credit rating...and the original default of your credit card will also still damage your credit rating.
Because the 6 days would not raise the garnishment and the 4 days of work lower the garnishment because the garnishment was too high a percentage of 4 days of work. Depends on pay periods/dates, and how the garnishment order is written. Different scenarios, ignoring mandatory taxes, assuming an hourly wage of $10, a weekly pay date, and a set garnishment of $150 a week, not to exceed 40% of net pay: $10 x 40 hours = $400 pay - $150 garnishment=$250 net to employee.