Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
sach tu » sach thu, cach tu, sach ty
hieu ve » hieu va, hieu van
va hanh » va thanh, va danh, ban hanh
su tien » su kien, su hien, tu tieng
ve cam » ve cham, ve cac, va cam
x hoi » xa hoi, o hoi, x ho
di su » doi su, ki su, da su

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach y) or (sach tu)) nang x hoi. hieu ve cam xuc ((va hanh) OR (van hanh)) di su tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach y) OR (sach tu)) nang x hoi. hieu ve cam xuc ((va hanh) OR (van hanh)) di su tien.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach y) or (sach tu)) nang x hoi. hieu ve cam xuc ((va hanh) OR (van hanh)) di su tien".
• Adding a wildcard symbol may retrieve word variants: tu ((sach y) or (sach tu)) nang x hoi. hieu ve cam xuc ((va hanh) OR (van hanh)) di su tien*.