Here is the full list of all 101 Little hidden city achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
the end of the game
find slide
find sculpture_rock
find gazebo
find water_motocycle
find telescope
find basketball
find inflatable pool
find cat
find tractor
find medical bed
find wheelchair
find power station
find flower_palicious
find electric car
find satellite_talk
find bicycle
find solar_battery
find statue
find pointer
find motorcycle
find air conditioning
find football_ball
find VOLGA
find swing
find TV
find boat_old
find traffic light
find camera
complete a level gas station
find haystack
find part of the train
find engine
find canister_2
find old car
find extinguisher
find equipment for garage
find logs
find muffler
find spare part
find barrel
find strut
find wheel_2
find wheel
find army trailer
find hovel
find soona
find Jack
find canister
pass_level_supermarket
find sink
find handbag_female
find steak_sibs
find bank_register
find fish
find moped
find bananas
find drawer
find basket
find bucket_washing brush
find soft toy
find eggplants
find stool
find carton
find jacket
find shoe
find trolley
find pac_products
find watermelon
find cake_shocolate
pass_level_country house
find light
find bucket of apples
find watering can
find plant_in_roof
find stairs
find potty
find log
find Boots
find tools
find watering can_2
pass_level_busstation
find newspaper
find suitcase_opened
find nameplate
find bicycle_old
find shoes
find bottles
find suitcase_02
find stroller
pass_level_apartment
find tube
find strap
find coat
find suitcase
find umbrella
find bag
find hat
find book
find magnifying_glass
start the game