Perhaps you should try some spelling variations:
hanh tai » thanh tai, hang tai, han tai
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
tai cuu » tai cuc, tai buu, tai cua
va hanh » van hanh, va thanh, va danh
cuu tre » cua tre, cau tren, cau treo
hai hoi » dai hoi, hai moi, hai hai
ky lang » ky nang, ky dang, ky tang
va cam » va cham, va cac, va cao
luc va » duc va, tuc va, loc va
ve cam » ve cham, ve cac, ve cai

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 ky lang ((hai hoi) or (dai hoc)). hieu ((ve cam) or (va cam)) luc va hanh tai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky lang ((hai hoi) OR (dai hoc)). hieu ((ve cam) OR (va cam)) luc va hanh tai cuu tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky lang ((hai hoi) or (dai hoc)). hieu ((ve cam) or (va cam)) luc va hanh tai cuu tre*.