Perhaps you should try some spelling variations:
hoc cong » hoc co, cac cong, hoc dung
truc van » truc va, truc ban, truc dan
thuc van » thuc vat, thuc dan, thuc va
cau tren » cu tren, dau tren, ca tren
hieu ve » hieu va, hieu van
hanh da » hanh dao, hanh dua, hanh va
ve cau » ke cau, va cau, ve cac
da cau » dat cau, va cau
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((nuoc cong) OR (hoc cong)) ky nang x hoi. hieu ve cau ((truc van) or (thuc van)) hanh da cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((nuoc cong) OR (hoc cong)) ky nang x hoi. hieu ve cau ((truc van) OR (thuc van)) hanh da cau tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((nuoc cong) OR (hoc cong)) ky nang x hoi. hieu ve cau ((truc van) or (thuc van)) hanh da cau tren*".