Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thanh ke » thanh ket, thanh ve, thanh de
ha thanh » va thanh, pham thanh, phan thanh
te sach » toc sach
xang co » nang co, lang co, tang co
su sach » so sach, vu sach
co hai » co dai, co hoi, o hai
tac ha » bac ha, tac da, tac xa
ve cac » vien cac
ke su » ke suu, ve su, ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (su sach)) ty xang co hai. hieu ((ve cac) OR (va cac)) tac ha thanh ke su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (su sach)) ty xang co hai. hieu ((ve cac) OR (va cac)) tac ha thanh ke su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (su sach)) ty xang co hai. hieu ((ve cac) OR (va cac)) tac ha thanh ke su triet".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (su sach)) ty xang co hai. hieu ((ve cac) OR (va cac)) tac ha thanh ke su triet*.