Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, lieu vien
vien cac » vien bach, vien dai, vien da
sang cho » danh cho, dung cho, sang tao
cho hoc » co hoc, khoa hoc
sach ty » sach tu, sach thu, xach tay
vuc van » luc van, thuc van, chuc van
duc van » duc va, duc tan, duc manh
hanh di » hanh vi, hanh de, hang di
cua cau » cua cac, cua chu, cua cay
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sach ty) or (sach y)) sang cho hoc. hieu vien cac ((vuc van) OR (duc van)) hanh di cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ty) OR (sach y)) sang cho hoc. hieu vien cac ((vuc van) OR (duc van)) hanh di cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ty) or (sach y)) sang cho hoc. hieu vien cac ((vuc van) OR (duc van)) hanh di cua cau*".