Perhaps you should try some spelling variations:
hoc kinh » hoc sinh, luoc kinh
danh vit » danh viet, dinh viet, dang viet
trung va » truong va, trang va, trung ha
truc va » thuc va, thuc vat
ca tren » cau tren, cu tren, la tren
hieu ve » hieu va, hieu van
van hoi » van hoa, van hoc, van hoe
ky dang » ky nang, ky danh
ky lang » ky nang, ky tang, tay lang
vit ca » viet ca, viet cau
ve cau » ke cau, va cau, ve cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc kinh ((ky lang) or (ky dang)) van hoi. hieu ve cau ((truc va) OR (trung va)) danh vit ca tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc kinh ((ky lang) OR (ky dang)) van hoi. hieu ve cau ((truc va) OR (trung va)) danh vit ca tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc kinh ((ky lang) or (ky dang)) van hoi. hieu ve cau ((truc va) OR (trung va)) danh vit ca tren".
• Adding a wildcard symbol may retrieve word variants: hoc kinh ((ky lang) or (ky dang)) van hoi. hieu ve cau ((truc va) OR (trung va)) danh vit ca tren*.