Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thanh ve » hanh ve, thanh va, thanh vien
xa thanh » va thanh, ha thanh, ta thanh
sach ty » sach tu, sach thu, xach tay
cac tac » cac toc, cac bac, cac dac
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
nang mo » nang meo, nang co, bang mo
ve cac » va cac, vien cac
tac xa » tuc xa, tac da
ve su » va 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) or (sach y)) ((nang mo) OR (nang ma)) hoi. hieu ve cac tac xa thanh ve su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach y)) ((nang mo) OR (nang ma)) hoi. hieu ve cac tac xa thanh ve su triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach y)) ((nang mo) OR (nang ma)) hoi. hieu ve cac tac xa thanh ve su triet*".