If you're looking for terrestrial DVB-T(2) reception and indoors in a room is too weak, the only practical option is to either go outdoors or, if favourable & desired, putting an antenna in the loft/attic.
I'm relatively lucky in that I can pick up DTT from a transmitter more than 70km away on my bedroom TV with a simple unamplified indoor aerial, but that's thanks to having favourable conditions (upstairs room, home lies quite high to surrounding near terrain and that the path from transmitter to receiver is almost line-of-sight).
In my experience, indoor amplified antennas are nearly always a waste of electric & money - there are some very occasional examples where they can help but more often than not they do no better than a reasonably well designed indoor aerial that makes the best of its inherent limitations. And where an indoor amplified antenna has been shown to work when unamplified aerials don't, they always are just about over the signal-to-noise threshold of reception and suffer easily from impulse noise, giving a "brittle" signal.
The Televes DAT BOSS antennas that rolfw linked to makes the best use of electrical amplification by not only integrating the amp within the active receiving element of the antenna (reducing losses & mismatches) but also putting it on an antenna that's designed to be put up high outdoors which is what really needs to be done before any "suck it & see" amplification should be done.
I must say though that in my experience, with the general ease of receiving out-of-area TV these days via satellite & internet, as well as DVB-T(2) allowing frequencies to be reused at closer distances than what was needed in the days of analogue broadcasting and thus blocking more distant signals from being received either often or occasionally, the general hobby of VHF & UHF TV DXing is largely gone now except for a few hardy souls that are still going.