Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
hanh ca » hanh cac, hanh cat, hanh cua
thuc va » thuc vat, thuc dan, thuc day
su sach » so sach, vu sach
van cau » van dau, van hau, van chat
cao hoi » cau hoi, co hoi, cao hoc
xuc va » duc va, tuc va, xac va
luc va » duc va, tuc va, loc va
ca cua » co cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang cao hoi. hieu van cau ((((xuc va) OR (luc va))) or (thuc va)) hanh ca cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang cao hoi. hieu van cau ((((xuc va) OR (luc va))) OR (thuc va)) hanh ca cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang cao hoi. hieu van cau ((((xuc va) OR (luc va))) or (thuc va)) hanh ca cua triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang cao hoi. hieu van cau ((((xuc va) OR (luc va))) or (thuc va)) hanh ca cua triet*.