df <- tibble("a" = 2:10,
"b" = c(1:5, NA, NA, 8:9),
"c" = c(3:5, NA, 7:11),
"d" = c(51:58, NA))
df
# A tibble: 9 x 4
a b c d
<int> <int> <int> <int>
1 2 1 3 51
2 3 2 4 52
3 4 3 5 53
4 5 4 NA 54
5 6 5 7 55
6 7 NA 8 56
7 8 NA 9 57
8 9 8 10 58
9 10 9 11 NA
# Drop row if NA in column b or c
df %>% drop_na(b, c)
# A tibble: 6 x 4
a b c d
<int> <int> <int> <int>
1 2 1 3 51
2 3 2 4 52
3 4 3 5 53
4 6 5 7 55
5 9 8 10 58
6 10 9 11 NA