You appear to have 5 anchors and 3 screws. I hope this isn't much of a rack, or that you're willing to go buy some
screws. Lag Bolts.
The things you are referring to as drywall screws appear to be screw-in drywall anchors, which then take a normal screw in the center of the anchor. They hold fairly well for a drywall anchor, but unless it's a very small, light rack with not much weight of equipment in it, not suitable.
The yellow anchors are for solid walls, - brick, concrete block or solid concrete. They are also used on drywall but don't hold very well compared to the whitesh/gray ones. In holes in solid masonry they will hold pretty well, but you only have 3 of them...
If you can line up with a stud, or better yet two studs, just use the screws directly, no anchors. Or use some better screws, since those thrown in with imported racks may be of fairly poor quality, as screws go.
I mount racks for work. They are not small, light nor lightly loaded. They have multiple thousands of dollars worth of stuff in them and it would be very bad if they fell down. Since racks rarely manage to have holes that hit two studs, or if they do, someone doesn't want the rack "just there" standard procedure is to screw a sheet of plywood to the studs, and screw the rack to the plywood. If we can hit one of the studs as well, great, but we don't need to at that point. Use the biggest lag bolt (diameter wise) that will fit the holes in the rack, and use at least 4 of them unless it's vanishingly small. Length-wise, if mounting to plywood, they just need to be a bit longer than the plywood is thick for full holding power. Use washers as well, and allow for the washers and rack thickness as well as the plywood thickness when selecting the length.