furtive russian
подложи́ть
lay, put, line, add, put some more, put furtively, plant (eg bomb)
подкла́дывать
lay, put, line, add, put some more, put furtively, plant (eg bomb)
подгля́дывать
peep, watch furtively, spy
ворова́тый
thievish, furtive, stealthy