If hubber score is less than 75 then there are 'nofollow' links on your hubs. When my score gets low - I look at my lowest score hubs and unpublish then - not delete, and fix those low score hubs to republish. Or just delete the lowest hubs that have a score of less than 60.
Your latest hub, "Money doesn’t growth on tree”50 - did you mean "Money doesn't grow on trees" that's the USA expression.
Good luck, and if you don't know nofollow - there are a lot of hubs that explains this.