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 va » lieu va, hieu qua
nang ra » nang ma, lang ra, nang va
nang ro » nang co, nang ho, nang rong
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 ro) OR (nang ra)) hoi. hieu va 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 ro) OR (nang ra)) hoi. hieu va 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 ro) OR (nang ra)) hoi. hieu va cac tac xa thanh ve su triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sach y)) ((nang ro) OR (nang ra)) hoi. hieu va cac tac xa thanh ve su triet*.