Perhaps you should try some spelling variations:
su sach » so sach, vu sach
xa hanh » xa thanh, xa khanh, va hanh
hoa hoi » khoa hoi, hoa hoc, hoa doi
cuu tre » cua tre, cau tren, cau treo
ve cam » ve cham, va cam, ve cai
ve cac » va cac, vien cac
ha hoi » ha noi, xa hoi, va hoi
vi cuu » vi luu, vinh cuu

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 _ lang ((ha hoi) or (hoa hoi)). hieu ((ve cam) or (ve cac)) tuc xa hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach _ lang ((ha hoi) OR (hoa hoi)). hieu ((ve cam) OR (ve cac)) tuc xa hanh vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: su sach _ lang ((ha hoi) or (hoa hoi)). hieu ((ve cam) or (ve cac)) tuc xa hanh vi cuu tre*.