Hi Guys,

Need some advise, I wanted to drill some mount for curtain rail, TV cabinet etc.
So I invested a cordless Bosch drill with hammer function.

On my 3rd room I drill for 1 hole used over 1hr - 2hr. It's ccrazy, then I curi Ayam by not drilling too deep for other hole (need 3 bracket, 1 full depth, another 2 I cut off nail and the plug to half).

Each time I drill, its smooth for 1.5cm around 0.6inch then it become damn hard , I think it's concrete, and 1.5cm it's cement?
I am using mansory drill bits and I try switching a few with my uncle itss still give similar result.
I also borrowed my uncle corded hammer drill, hit 1.5cm then become very hard to drill like not moving..

Aircond installer come they also complaining my wall is very hard to drill which they use a lot force, they said normally few min 1 hole they did, my hse like near half n hr for 1 hole.

Need some advise as below.
1. If I just drill 1.5cm and cut plug with screw, will it dangerous? cause I not sure how much weight it can take.
2. If I shall drill full 3cm (normal screw n plug length) any tips to proceed the hard rendered concrete I assume? not sure is my drill bit problem or drill or skill.. haha