White clothing in particular is vulnerable to going grey or yellow over time?

The white cloths didn't mixing with any other colour.

White clothing in particular is vulnerable to going grey or yellow over time. This can be caused by a number of things. The most common is mixing your whites and colors. Even if you do not have many white clothes, make a point of washing them separately. Also, make sure you are using enough detergent, as not putting enough in can lead to residue remaining in the load. Try washing your clothes at a higher temperature also, as this will help to eliminate grey and yellow staining.