Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
cua triet » cua viet, su triet, va triet
dua tren » dung tren
vu sach » vu bach, su sach, vu khach
sach ty » sach y, sach tu, sach thu
dan bac » dan ba, van bac, dong bac
van bao » van ban, van dao
va hanh » van hanh, va thanh, va danh
xang o » lang o, tang o, dang o
o hoi » co hoi, o hoc, o hai

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 ty xang o hoi. hieu ((dan bac) or (van bao)) duc va hanh thai ((dua tren) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty xang o hoi. hieu ((dan bac) OR (van bao)) duc va hanh thai ((dua tren) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: vu sach ty xang o hoi. hieu ((dan bac) or (van bao)) duc va hanh thai ((dua tren) or (cua triet))*.