Perhaps you should try some spelling variations:
nuoc sach » nguoi sach, cuoc cach, cuon sach
sach dao » lanh dao
hoc sach » hoc sinh, hoc cac, hoc anh
trinh co » trinh do, trinh cong, trinh hoa
te sach » toc sach
dao cao » dao tao, bao cao, tao cao
cao khi » cao khai, cao thi, cac khi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( te sach dao cao khi đong luc ) or ( ((nuoc sach) or (hoc sach)) trinh co khi đong luc ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach dao cao khi đong luc ) OR ( ((nuoc sach) OR (hoc sach)) trinh co khi đong luc )).
• Adding a wildcard symbol may retrieve word variants: (( te sach dao cao khi đong luc ) or ( ((nuoc sach) or (hoc sach)) trinh co khi đong luc ))*.