Perhaps you should try some spelling variations:
sach nang » cach mang, sach dung, sach danh
cham truc » cau truc, nham thuc, pham thuc
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
truc van » truc va, thuc van, truc ban
van cham » van chat, van tham, va cham
vu sach » vu bach, su sach, vu khach
quan va » quan vi, quan ha, luan va
quan ma » quang ma, quan ha, quan xa
di cua » dai cua, doi cua, do cua
de cua » le cua, te cua, dieu cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach nang ((quan ma) OR (quan va)) hoi. hieu van cham truc van hanh ((di cua) or (de cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach nang ((quan ma) OR (quan va)) hoi. hieu van cham truc van hanh ((di cua) OR (de cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach nang ((quan ma) OR (quan va)) hoi. hieu van cham truc van hanh ((di cua) or (de cua)) tre".
• Adding a wildcard symbol may retrieve word variants: vu sach nang ((quan ma) OR (quan va)) hoi. hieu van cham truc van hanh ((di cua) or (de cua)) tre*.