Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan
dang xay » dang van, van xay
xay hoi » xa hoi, tay hoi, cay phoi
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
vu sach » vu bach, su sach, vu khach
vai su » va su, lai su, tai su
van su » dan su
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: vu sach ky dang xay hoi. hieu va am ((thuc dan) or (thuc vat)) hanh ((vai su) OR (van su)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky dang xay hoi. hieu va am ((thuc dan) OR (thuc vat)) hanh ((vai su) OR (van su)) triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky dang xay hoi. hieu va am ((thuc dan) or (thuc vat)) hanh ((vai su) OR (van su)) triet*".