El Symbols is right that there's 'diving', falling down to look like you've been fouled in an attempt to get a free kick or penalty and maybe get the opposing player unfairly booked or even sent off. and then as you say say, there's the boxing association where, you're right, it means throwing a fight. I don't see any evidence of the latter going on during the tournament but the former is a real problem.
Although some are better at it than others.
Have to agree with symbols again, re the Portugal game. No way was it 'thrown'. I'm sure it's happened in the past and I remember hearing stories a few world cups ago of pressure being put out on some South American side by big organised crime affiliated gamblers but I don't think anything actually happened. The only really high profile instances of it that I know of for sure have been in Italy, which is currently going through a big scandal about it, but that only effected its domestic league. Maybe I'm being naive but I really don't think it's that widespread a concern.