Does anyone have an idea - How to book into Specific fareclass? like K, T, L,,

I am planning my summer flights, and many sites (include nwa.com)
showing only 'M' class -Which is really worthless for the money.
(No upgrade, No bonus EQM)
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When I search on KVS, and seatcounter, there's "T"class available.

-of course inorder to book into certatin class needs to meet
few qualification such as "stay periods, city pairs"....

but I was able to book on cheaper fareclass past few years under similer
trip schedule, however this year is very difficult.