Perhaps you should try some spelling variations:
su triet » su viet, su tien
sach thu » sach thue, sach thieu, sach tham
thu hanh » thuc hanh, thu thanh, thuy hanh
ve triet » va trien
va triet » va thiet, va trien, cua triet
hanh hai » thanh hai, nhanh hai, hang hai
tu sach » thu sach, su sach, te sach
thuc va » thuc vat, thuc dan, thuc day
hieu va » lieu va, hieu qua
hanh xa » hanh va, hanh ma, hanh xu
va hanh » van hanh, va thanh, va danh
va am » va lam, va cam

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