Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thanh hai » thanh phan, thanh hoa, thanh san
dang xay » dang van, van xay
lanh hai » manh hai, lang chai, lanh dao
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
xay hoi » xa hoi, tay hoi, cay phoi
ky dang » ky nang, ky danh
ve 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: vu sach ky dang xay hoi. hieu ((ve cac) OR (va cac)) duc tan ((lanh hai) or (thanh hai)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky dang xay hoi. hieu ((ve cac) OR (va cac)) duc tan ((lanh hai) OR (thanh hai)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky dang xay hoi. hieu ((ve cac) OR (va cac)) duc tan ((lanh hai) or (thanh hai)) cua triet".
• Adding a wildcard symbol may retrieve word variants: vu sach ky dang xay hoi. hieu ((ve cac) OR (va cac)) duc tan ((lanh hai) or (thanh hai)) cua triet*.