Perhaps you should try some spelling variations:
hanh trinh » hanh chinh
trinh nghe » trinh nghien, trinh he, trinh nha
tranh thi » tranh thai, tran thi, trinh thi
tu hanh » du hanh, lu hanh, thuc hanh
tu canh » thu canh, tu chanh, tu can
diu hoc » du hoc, lieu hoc, dich hoc
dia hoc » dia oc, dich hoc, dien hoc
di hoc » li hoc, du hoc, vi hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tu hanh trinh nghe ((di hoc) OR (dai hoc)) ) or ( tu canh tranh thi ((diu hoc) or (dia hoc)) ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu hanh trinh nghe ((di hoc) OR (dai hoc)) ) OR ( tu canh tranh thi ((diu hoc) OR (dia hoc)) )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tu hanh trinh nghe ((di hoc) OR (dai hoc)) ) or ( tu canh tranh thi ((diu hoc) or (dia hoc)) ))".
• Adding a wildcard symbol may retrieve word variants: (( tu hanh trinh nghe ((di hoc) OR (dai hoc)) ) or ( tu canh tranh thi ((diu hoc) or (dia hoc)) ))*.