Perhaps you should try some spelling variations:
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
ty nang » ky nang, ty xang, ly nang
ty hang » ly hang, ty xang, thi hang
vien da » vien dai
vi cua » vai cua, di cua
cua te » cua tu
hien » bien, tien, dien

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 ((ty nang) or (ty hang)) xa hoi. hieu ((vien da) OR (hien dai)) thuc van hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ty nang) OR (ty hang)) xa hoi. hieu ((vien da) OR (hien dai)) thuc van hanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ty nang) or (ty hang)) xa hoi. hieu ((vien da) OR (hien dai)) thuc van hanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((ty nang) or (ty hang)) xa hoi. hieu ((vien da) OR (hien dai)) thuc van hanh vi cua te*.