Those screw in fixings are pretty horrible, I'd avoid at all cost for putting up anything. They make a huge hole, can't hold enough weight for anything heavy and they are overkill for anything lite. If you must use them make sure you use the metal ones for a skimmed wall.
My go to for fixings attaching directly to plasterboard are:
- lite to medium weight use a good quality multi surface plug like Fisher Duo Power, you can use them in plasterboard, block or brick. One plug to rule them all and no need for anything else. I have put up all sorts with these from mirrors to decorative shelving (e.g. not for heavy items like books).
- heavier items use metal wall anchors, make sure you set them correctly with the proper tool. These should hold up all but the heaviest of items like a kitchen cabinet.
If you can screw into a stud then do so but the chances are the studs are not where you need them.
If you have a block wall behind you have the option to go directly into the wall. For something that is mid-heavy you can do the 'two plug method' which is one plug in the wall and the other in the plasterboard directly in front of it. The plug in the wall holds the weight and the plug in the plasterboard supports it so you don't bow or crack the board when it all gets tightened up. You drill one long hole all the way through the board and block behind, tap the first plug through using a partly threaded screw and then put the second plug into the plasterboard. You then attach the piece to the wall using a long screw through both plugs.
Like this:
https://youtu.be/87hOAnt9d5s?t=421
If its really heavy like a kitchen cabinet, the proper fixing for the job is Core Fix. It's essentially the same concept but its one purpose made long plug, a metal feral which you insert after you have put in the plug in and you use the supplied long screw go through into the block behind. These are much stronger than the above method.