How to compose writings with abstract ideas?

I consider my standard of English as in the advance level and I am generally quite good in writing compositions that has a specific purposes (e.g. reserach paper,informative compositions) but I get the writer's block when I have to write pieces with abstract ideas (e.g. about my feelings, philosphical issues). Could someone make any suggestions on how to improve my skills in this area? Could someone also suggest a faster way to learn new vocabularies other than by rote learning?