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
te sach » toc sach
sach ty » sach y, sach tu, sach thu
xang co » nang co, lang co, tang co
cac duc » cac du, cao duc, cac dac
duc van » duc va, duc tan, duc manh
vi cua » vai cua, di 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 ty xang co hoc. hieu vien cac duc van hanh ((vi cua) or (dai cua)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty xang co hoc. hieu vien cac duc van hanh ((vi cua) OR (dai cua)) cau*.