Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
su triet » su viet, su tien, ve triet
thanh vi » thanh va, thanh ve, nhanh vi
cac tac » cac toc, cac bac, cac dac
tu sach » thu sach, su sach, te sach
ty nang » ky nang, ty xang, ty hang
hieu ve » hieu va, hieu van
nang o » nang co, nang ho, nang ro
ve cac » va cac, vien cac
tac xa » tuc xa, tac da
o hai » co hai, so hai, o lai

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) or (thuoc sach)) ty nang o hai. hieu ve cac tac xa ((thanh vi) OR (hanh vi)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ty nang o hai. hieu ve cac tac xa ((thanh vi) OR (hanh vi)) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thuoc sach)) ty nang o hai. hieu ve cac tac xa ((thanh vi) OR (hanh vi)) su triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ty nang o hai. hieu ve cac tac xa ((thanh vi) OR (hanh vi)) su triet*.