Perhaps you should try some spelling variations:
vien cac » vien bach, vien dai, vien da
van hanh » van thanh, ban hanh, van anh
cau treo » cau theo, cau tren, cau triet
su sach » so sach, vu sach
tang xa » trang xa, tang ma, lang xa
tuc van » thuc van, truc van, tuc va
sach 7 » sach y, sach 2
7 tang » 6 tang
ve cam » ve cham, ve cac, va cam
vi cau » va cau, ve cau, di cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach 7 tang xa hoi. hieu ((ve cam) or (vien cac)) tuc van hanh vi cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach 7 tang xa hoi. hieu ((ve cam) OR (vien cac)) tuc van hanh vi cau treo.
• Adding a wildcard symbol may retrieve word variants: su sach 7 tang xa hoi. hieu ((ve cam) or (vien cac)) tuc van hanh vi cau treo*.