Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, lieu vien
vien cac » vien bach, vien dai, vien da
van hanh » van thanh, ban hanh, van anh
toc sach » hoc sach, doc sach, thuoc sach
thi nang » thi cong, ki nang, thi hanh
nang cho » nang chon, ngang cho, nang cao
vung van » vung va, dung van, vung ven
cac vung » cac ung, cac chung, cach dung
cho hoc » co hoc, khoa hoc
vi cua » vai cua
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: ((te sach) OR (toc sach)) thi nang cho hoc. hieu vien cac vung van hanh ((vi cua) or (di cua)) chu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) thi nang cho hoc. hieu vien cac vung van hanh ((vi cua) OR (di cua)) chu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) thi nang cho hoc. hieu vien cac vung van hanh ((vi cua) or (di cua)) chu*".