英文關鍵字
adventure
army
background
business
check
control
danger
detector
device
discovery
electrical
electronic
equipment
field
find
gate
gold
history
hobby
industry
inspection
isolated
looking
lost
machine
man
metal
military
money
object
old
outdoor
outdoors
people
protection
safety
sand
scan
scanner
sea
search
searching
seeker
sensor
steel
system
technology
travel
treasure
water
white