Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
phan duc » phan tu, phan dau, tran duc
thi hang » thi hanh, thi nang, thi hong
van anh » van thanh, tuan anh, van minh
tu sach » thu sach, su sach, te sach
hieu ke » hieu kem, chieu ke, hieu ky
ty hang » ly hang, ty xang, thu hang
anh vi » hanh vi, anh va, anh ve
vi su » va su, ve su, ki 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 ((ty hang) OR (thi hang)) xa hoi. hieu ke ((phan duc) or (pham duc)) van anh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty hang) OR (thi hang)) xa hoi. hieu ke ((phan duc) OR (pham duc)) van anh vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty hang) OR (thi hang)) xa hoi. hieu ke ((phan duc) or (pham duc)) van anh vi su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty hang) OR (thi hang)) xa hoi. hieu ke ((phan duc) or (pham duc)) van anh vi su triet*.