Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
dang thai » dang thi, dang hai, dang khai
hanh dai » hanh tai, hanh dao, vanh dai
ve triet » va trien, su triet
dang tai » dung tai, hang tai, dang thi
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
toc va » hoc va, toc ta, loc va
tuc va » thuc va, truc va, tuc xa
dai ve » dap ve, dau ve, dai va
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ky ((dang tai) OR (dang thai)) hai. hieu ve cac ((toc va) or (tuc va)) hanh dai ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky ((dang tai) OR (dang thai)) hai. hieu ve cac ((toc va) OR (tuc va)) hanh dai ve triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky ((dang tai) OR (dang thai)) hai. hieu ve cac ((toc va) or (tuc va)) hanh dai ve triet".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky ((dang tai) OR (dang thai)) hai. hieu ve cac ((toc va) or (tuc va)) hanh dai ve triet*.