Perhaps you should try some spelling variations:
kham thuc » nham thuc, pham thuc, tham thuc
cua triet » cua viet, su triet, va triet
vat hanh » vat thanh, van hanh, va hanh
sach nay » sach hay, sach vay, sach nang
sach tay » xach tay, sach hay, sach tai
hieu su » hieu sau, tieu su, hieu so
hanh va » hang va, hanh vi
hieu vu » hieu va, hieu ve, dieu vu
lang xa » lang ha, dang xay, lang van
va cua » va chua, via cua, ca cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach tay) or (sach nay)) lang xa hoi. ((hieu vu) OR (hieu su)) kham thuc vat hanh va cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach tay) OR (sach nay)) lang xa hoi. ((hieu vu) OR (hieu su)) kham thuc vat hanh va cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach tay) or (sach nay)) lang xa hoi. ((hieu vu) OR (hieu su)) kham thuc vat hanh va cua triet".
• Adding a wildcard symbol may retrieve word variants: te ((sach tay) or (sach nay)) lang xa hoi. ((hieu vu) OR (hieu su)) kham thuc vat hanh va cua triet*.